I have a vision problem and can barely read low-contrast print, even the light colors on your Web site. Any ideas for how I and others can solve this problem? I use a Mac and the Firefox Web browser.

A: If your Mac is running the Leopard or Snow Leopard operating systems, you can use an onscreen slider control or keyboard commands to enhance the contrast. You can even switch the display to white-on-black, which really boosts the effect. This works system-wide. These settings are found in System Preferences, under the Universal Access preference, in the tab called “Seeing,” in the section called “Display.”

The new Windows 7 also has a similar feature that applies a “high contrast theme” when you press a certain key combination. It can be enabled or disabled in the Control Panel, under Ease of Access. You click on “Ease of Access Center,” and then “Make the computer easier to see.”

Where can I download the Windows 7 Home Premium upgrade edition for my Vista Home Premium computer?

A: Windows 7 can be downloaded at http://store.microsoft.com/home.aspx. And, after you’ve installed it, you can upgrade to higher versions anytime, if you like, for a fee. This is called the Windows Anytime Upgrade, and is explained at this site: http://bit.ly/VrV58.

Do you know if the new Windows 7 Home Premium will be offered at less than the retail price of $120 to current Vista PC owners who wish to upgrade?

A: That $120 price is the upgrade price for Vista owners moving to Windows 7 Home Premium, though of course some retailers might discount it. The “full,” or non-upgrade, edition of Home Premium lists for $200. Microsoft did run a sale on Windows 7 pre-orders earlier this year, but that’s over.

You can also get a Windows 7 upgrade from participating PC makers free, or for a nominal fee, if you buy a new PC equipped with Vista before the end of January, 2010, or bought one after June 26, 2009. For the latter offer, consult: http://bit.ly/rjAz4.

You can find Mossberg’s Mailbox, and my other columns, online, free, at the All Things Digital web site, http://walt.allthingsd.com.

Corrections & Amplifications

An earlier version of this column erroneously stated that Windows 7 had to be purchased on a disk.

There are lots of reliable online sellers of laptops, and online buying is fine, provided you have somehow handled the machine and are familiar enough with it to be sure it’s the one you (or, in this case, your lucky wife) will be happy owning. In the case of Apple, a company whose products are rarely deeply discounted by third-party sellers, it often makes sense for online buyers to use the company’s own online store, at store.apple.com. I have found Apple’s online store to be easy to use, secure and reliable. And you get some minor benefits at the physical Apple stores if you buy directly from Apple.

However, other major online sellers with equally good reputations also carry Macs, and some do shave the prices. One good example I have used happily is amazon.com, which carries the latest MacBook Pros at discounts ranging from $5 to over $100, depending on model.

How can I set parental controls in Firefox?

The Firefox Web browser doesn’t have built-in parental controls. Its maker, Mozilla, notes that version 3.0 or later of the browser does support some of the parental-control features included in Windows Vista. But if you don’t have Vista, or want different controls, there are some add-ons for Firefox that provide these.

Among the ones Mozilla suggests using are Glubble for Families, and ProCon Latte. More information is at: support.mozilla.com/en-US/kb/Parental+controls.

In your recent Firefox review, you said Internet Explorer has a private browsing mode that doesn’t record your history or tracks while surfing. But I can’t find how to turn it on.

The feature, which is called InPrivate Browsing, is only available in the latest version of IE, called IE8. You turn it on by either selecting that option from the Safety button at the upper right, or from the Tools menu in the Menu Bar if you have chosen to make that bar visible. Once you do, an “InPrivate” label appears at the top left corner of the browser and a page appears explaining that the browser won’t record on your own PC certain records of what you do in that browsing session. There’s an additional privacy mode, available from the same two drop-down menus, called “InPrivate Filtering,” which goes further. It blocks Web sites you go to from saving certain records of your presence there on their own servers. InPrivate browsing lasts until you close the InPrivate browsing window.

When you reviewed the latest Safari Web browser awhile back, you complained that Apple had repositioned the tabs in a way that made them harder to see. A friend said that’s no longer true. Is he right?

Yes. After getting a lot of negative reaction, Apple changed Safari 4’s design so the tabs are displayed in the previous manner, below the toolbar, instead of at the very top. The company also made more visible the page-loading indicator, though I personally still prefer the indicator style used in prior versions.

In your column last week, you recommended add-on software to search documents for key words in Windows XP. Is there any similar software that will do the same for Macs?

It’s unnecessary on Mac because the Mac operating system comes with a fast, comprehensive search system called Spotlight that’s built right in. Windows Vista also has a very good search system built in. The reason I recommended add-on software for Windows XP is that I consider XP’s built-in search to be slow and inferior to those in these two newer operating systems.

You can find Mossberg’s Mailbox, and my other columns, online for free at the All Things Digital Web site, http://walt.allthingsd.com.

Here are a few questions about computers I’ve received recently from people like you, and my answers. I have edited and restated the questions a bit, for readability.

I switched from PC to Mac a year ago, but now I am thinking of adding a Windows laptop. If I do, what kind of compatibility problem would I have? I would be using the laptop mostly to write, to send/receive email and to Web browse.

In the old days, there were compatibility problems, but most of those have gone away. Based on your simple predicted usage, I’d say that you should be fine. For instance, both Macs and PCs can interchangeably open and edit all of the major file types — JPG pictures, MP3 music, Microsoft Office documents, Adobe PDF files, etc. Email and instant messages can, of course, be exchanged between the two platforms, even if you are using different programs. And Macs understand Windows file extensions. Also, you can use both platforms simultaneously on the same home network to access the Internet.

In some cases, you might need different programs to open the same files on the two platforms. But even that obstacle has greatly diminished. For instance, programs like the Firefox and Safari Web browsers, Adobe Reader, iTunes, Microsoft Office, Google Earth, Picasa, Photoshop and many others come in native versions for both platforms that can handle the same files. And, of course, Web-based programs like Gmail and Yahoo Mail work on both. Sometimes, the same programs have different features and user interfaces on Windows and Macs, but I haven’t found these differences hard to master.

The biggest problems for average users are Quicken, whose Mac version is inferior and incompatible; Internet Explorer, which is no longer made for the Mac; and Microsoft Outlook, which is replaced on the Mac by a program called Entourage that is similar but uses a different file format. And networking can be tricky. In general, the Mac does a better job of seeing Windows PCs on a network than Windows does of seeing Macs.

I use Outlook Express for my email, and I store a lot of mail in local folders. Is there a simple way to back these up? If I buy a new computer, can they be transferred?

Yes. There are two methods. One is a manual method, which Microsoft explains in a detailed document at this Web site: support.microsoft.com/kb/270670.

The other, quicker, method is to obtain one of several utility programs that can back up your Outlook Express data and, in some cases, allow you to transfer it to another PC. I haven’t tested these in years, and thus can’t recommend one over another. But one example is a free program called Outlook Express Backup, which can be found at genie-soft.com/products/oeb. Another is a $40 program called Outlook Express Backup Wizard, which can be found at: outlook-express-backup.com.

Do you know of an iPhone GPS application that speaks directions? It would make the iPhone similar to a TomTom or Garvin GPS unit.

A: No, but Apple recently announced that, under its new 3.0 operating system for the iPhone, such programs will be possible. Several companies are believed to be working on them, and I expect them to be available later in the year. The reason none exist yet is partly legal, having to do with the licensing of the underlying maps.

• You can find Mossberg’s Mailbox, and my other columns, online free of charge at the new All Things Digital Web site, http://walt.allthingsd.com.

Here are a few questions about computers I’ve received recently from people like you, and my answers. I have edited and restated the questions a bit, for readability.

I need to use Microsoft Publisher documents on my MacBook. Unfortunately, I can’t figure out how to do this. I have tried to run it on Microsoft Word, but this didn’t work.

As far as I know, neither Microsoft nor Apple nor anyone else makes a native Mac program that can open or edit Microsoft Publisher documents, which use their own special format, rather than any common cross-platform format.

However, there may be some workarounds. If you own or can borrow a PC and a copy of Microsoft Publisher, you could export the documents as PDF files from within Publisher, and then open them on a Mac. Or you could run Publisher itself on your MacBook, since Macs can run Windows and Windows programs, if you buy and install Windows.

Your Mossberg Solution column recently recommended an add-on for Firefox called Surf Canyon that improves searches. But I am wondering if it’s safe to use, since it is labeled “beta.”

I have been using Surf Canyon in Firefox for months, without any problems. (It also works in Internet Explorer.) You are correct that it’s a beta, but that label doesn’t usually mean a product is unsafe, just that it’s incomplete or unpolished. In the old days, a “beta” product was usually pretty flaky and available only to a very small number of testers until the kinks were worked out. Now, especially with Web-related products, a “beta” is often just another word for version 1.0 of a product. It is open to all, and may not work perfectly, but is usually not dangerous to your computer.

Is there a legal way to use a smartphone as a modem for a laptop?

Yes, indeed. It depends on your carrier, and your plan, and your phone, but it can be done, perfectly legally, either using a cable or Bluetooth wireless to connect the phone to the laptop. Note that, depending on your plan, the carrier may well charge you an added monthly fee for this privilege. Also, the speed of your connection may be a bit slower than the speed you’d get from a cellular data card you insert directly into the laptop or from one that’s built in.

• You can find Mossberg’s Mailbox, and my other columns, online free of charge at the new All Things Digital Web site, http://walt.allthingsd.com.

I have Firefox on my home laptop, but Internet Explorer on my office laptop. Can I transfer my Firefox bookmarks on my home computer to IE on my office computer using the Foxmarks bookmark-synchronization service you recommended? And how would I go about doing it?

Yes. You start by uploading your bookmarks from Firefox at home to your Foxmarks Web account, using the Firefox version of Foxmarks. That will establish the bookmark collection on the Web site as identical to your Firefox collection. Then, you install the IE version of Foxmarks on your office computer, and, when it prompts you to sync, you can either merge the Web-based bookmarks you previously uploaded from Firefox with the ones already on IE, or choose the option to overwrite the IE bookmarks entirely with the ones online.

Does the Foxmarks service work with AOL’s browser bookmarks?

AOL’s browser is not supported. Neither are some other browsers, such as Opera or Google’s Chrome. Foxmarks currently comes in versions only for Internet Explorer, Firefox and Safari (Mac version only). The Firefox version also works with Flock, which is a browser heavily based on Firefox.

Do you have any idea what the realistic hardware requirements will be to run Windows 7?

Microsoft hasn’t announced these yet. But the requirements for the current beta version are likely to be similar to those for the final release. The beta hardware requirements are: a 1 GHz 32-bit or 64-bit processor; 1 GB of system memory; 16 GB of available disk space; support for DirectX 9 graphics with 128 MB memory available for graphics; and a DVD-R/W Drive.

In the past, Microsoft’s minimum requirements have tended to understate what’s needed to run Windows well, even when doing typical tasks. It’s too early to say if this will be true of Windows 7. But I can say that, in my testing so far, the beta of Windows 7 runs much more quickly and smoothly than Vista on the same hardware.

• You can find Mossberg’s Mailbox, and my other columns, online free of charge at the new All Things Digital Web site, http://walt.allthingsd.com.

If I buy a PC with an AMD processor instead of an Intel one, will I run into any compatibility issues with common software like Vista or Office 2007?

No, as long as the AMD processor, and/or its accompanying graphics and other chips, called a “chip set,” are rated as being able to handle the graphics in the version of Vista you are buying. Each chip company makes some low-end models that handle certain tasks more slowly than their mainstream or top-of-line models. And gamers are often particular about which chip sets they buy. But, in my experience, roughly comparable AMD and Intel processors and chip sets are equally compatible with common software like Office and Windows.

I have been using the Netscape Web browser for years. I am interested in shifting to using the Firefox browser. How do I transfer my extensive list of book marks from Netscape to Firefox?

Firefox will import your Netscape bookmarks automatically during the installation process, just as it can automatically import bookmarks from other browsers like Internet Explorer, Safari and Opera.

Friends who use Macs tell me they have a removable backup device that backs up their entire hard drive, including programs. Is there something similar for PCs?

You appear to be referring to Time Capsule, which is an Apple hardware product that combines a hard disk and a wireless base station and is meant to work with the Mac’s built-in Time Machine automated backup feature. The answer is that there are many backup drives for Windows PCs, and that lots of them work with Macs as well. All the major hard-disk makers sell external hard disks that connect to a PC either directly, or over a network, and which come with relatively simple backup programs. Some of these programs will do complete, automated backups of everything on your PC, including applications. Even Apple’s Time Capsule can be used to back up files from Windows PCs, though it doesn’t come with Windows backup software, and setting it up for Windows is slightly trickier than doing so on a Mac.

You can find Mossberg’s Mailbox and my other columns online free at the All Things Digital Web site, http://walt.allthingsd.com.

Do you know of a free or inexpensive program that will overwrite hard drives? My husband and I have updated to new computers, leaving us with two hard drives that have sensitive data that we would like to erase before disposing of them.

There’s a $20 program for Windows called Window Washer from Webroot that will wipe an entire hard disk so that its data is unrecoverable. Its maker calls this process “bleaching.” In cases where you don’t want to completely wipe a hard disk, the program can also securely erase individual files and folders, and can remove all traces of browser activity. I have tested it, and I can recommend it. You can get it at Webroot.com.

There are numerous other Windows file wipers, some of which may be free, though I haven’t tested them. To find these others, go to download.com and enter “file wiper” in the search box.

Since downloading the new Firefox browser, the panel at the top that shows the Web address and the back and forward buttons has disappeared. How do I get it back?

That panel is called the Navigation Bar and it can be turned on and off. It sounds like it somehow got turned off on your computer. To switch it on again, go to the “View” menu, select “Toolbars” and then click on “Navigation Bar.” The missing panel should reappear, and the next time you view that menu option, you will notice a check mark next to “Navigation Bar,” indicating it is on.

You can also use the same technique to switch the Bookmarks Toolbar on and off.

I have switched to Mac recently and never want to use Windows again. But the program I miss using on Windows the most is Microsoft Money. Do you know any way to make this program run on my Mac?

Microsoft (MSFT) doesn’t make a Mac version of Money.

However, all current Macs can run Windows and Windows programs. I suggest you pick up a copy of one of two programs — Parallels Desktop or VMWare Fusion. Both allow you to run Windows programs right alongside your Mac programs, even without displaying the Windows desktop. Microsoft Money would just appear in its own window, as if it were another Mac program.

This method works well, but it carries a price. Fusion and Parallels cost around $60-$70 each, plus you will have to buy and install a full, fresh, boxed copy of Windows.

• You can find Mossberg’s Mailbox, and my other columns, online for free at the new All Things Digital Web site, http://walt.allthingsd.com.

Does any PC manufacturer offer an option to order a Windows (MSFT) PC without any extra software preinstalled?

Dell’s XPS models can be ordered without most preloaded third-party software if you are very careful about clicking all the “no” options when ordering online. But you still are likely to find yourself with Dell’s (DELL) own sometimes annoying networking software.

I have two Windows machines, one for work and one for home. Both use Outlook for email. How can I best transfer many emails from the machine at work to the one at home and still be able to read them in Outlook — without forwarding them all?

Outlook has an “Import and Export” function that will allow you to export any of your email folders to, say, a transferable medium such as an external hard disk or flash drive. You can then take this removable medium to the home computer, plug it in, fire up Outlook, and then import the folder you had exported earlier at work. You can find these import and export functions under Outlook’s File menu.

Can Internet Explorer and Firefox 3.0 coexist on the same computer?

Yes. In fact, you can have 2, 3, or 4 different Web browsers installed on the same personal computer, whether Windows or Mac (AAPL). You can even run different browsers simultaneously. For instance, as I type this, I am running IE 7, Firefox 3.0 and Safari 3.0 on the same computer at the same time.

The only slight hassle is that you will have to decide which to designate as the default browser, the one that launches when, say, you click on a link in an email.

• You can find Mossberg’s Mailbox, and my other columns, online for free at the new All Things Digital web site, http://walt.allthingsd.com.

After reading your positive review, I downloaded Firefox 3.0, only to discover that some of my favorite add-ons, including a search toolbar, are incompatible. What can I do about this?

Wait. As I noted in the review, when major new versions of Firefox come out, it takes a while for some of the many add-ons for the browser to be updated so they are compatible with the new version. Because these are written by a very large number of different companies and individuals, the process will be gradual, and some will be updated more quickly than others.

As for search toolbars, like those from Google (GOOG) and Yahoo (YHOO), I doubt that most people still need them. When they first came out, these toolbars provided things the top browsers lacked: a permanent search box, pop-up blocking and a few other useful features. But all the major browsers now provide these things without requiring the installation of any external toolbar. The companies that make the toolbars can use them to sell advertising or attract you to their search engines. But, for many users today, they are redundant.

I don’t want to run antivirus software constantly, but I would like to periodically run a program that could scan my computer and remove viruses and the like. Does such a program exist?

Yes. Here’s one example. Microsoft (MSFT) makes a small, free program called the Malicious Software Removal Tool that looks for, and tries to remove, a limited number of the worst examples of malicious software. It can be downloaded at www.microsoft.com/security/malwareremove.

However, this isn’t a comprehensive antivirus program. Microsoft says it detects and removes only “specific, prevalent malicious software,” and advises that “You should also use up-to-date antivirus software to help protect your computer from other malicious software.”

I am in the market for a laptop. I was considering a Dell (DELL) or an H-P (HPQ) but have learned that Apples now run Windows. I have financial (Quicken) and other business files (Excel, Word and PowerPoint) that would need to be transferred to the new computer. Would this be possible on an Apple (AAPL)?

Yes, in the same ways you could transfer files from one Windows PC to another. For example, you could burn them to a CD or DVD, copy them to an external USB drive, or transfer them over a network or via the Internet. In fact, if you buy your Mac at an Apple retail store, the store’s staff will move your files over free, or for a modest fee, depending on which folders, and how many, you want transferred.

Once the files are on the Mac, you can either use native Mac programs to read and/or modify them, or you can install Windows and run your usual Windows programs to handle the files.

For instance, even if you never installed Windows on an Apple, your Excel, Word and PowerPoint files could be used in the Mac version of Microsoft Office. However, the Mac version of Quicken isn’t as compatible with the Windows version’s files. So, for Quicken, I suggest installing Windows on the Mac and running the Windows version of Quicken.

• You can find Mossberg’s Mailbox, and my other columns, online for free at the new All Things Digital web site, http://walt.allthingsd.com.