In a recent column, you said Microsoft had imposed a legal prohibition on running the Home versions of Windows Vista on a Macintosh using virtualization programs like Parallels and Fusion. Does the same prohibition apply if you are installing Vista using Apple’s Boot Camp software?

No, because Boot Camp doesn’t create a virtual Windows computer — it actually carves out part of an Intel-based Macintosh’s hard disk and turns it into a full-blown physical Windows computer. To Windows, a Mac configured this way looks just like any Dell or Hewlett-Packard or other standard Windows computer. Boot Camp is free, but, such as Parallels and Fusion, it requires you to purchase a full, boxed copy of Windows to install.

The upside of the Boot Camp approach is that, when you are running Windows on the Mac, all of the computer’s hardware is devoted to Windows, because the Mac’s own operating system, OS X, isn’t running at all and a portion of the hard disk is reserved for the exclusive use of Windows. The downside is that you cannot run the two operating systems simultaneously, as you can with virtual solutions such as Parallels and Fusion. To switch between using Windows programs and Mac programs, you must restart the machine while holding down the Option key and then choose whether you want it to boot into Windows or Mac OS X. Both Parallels and Fusion can, however, use a Boot Camp Windows installation to create a virtual version of Windows that can be used simultaneously with the Mac OS.

If you install Boot Camp on a well-equipped Mac model, it can become a blazing fast Vista computer. A few days ago I bought a top-of-the-line model of Apple’s new iMac line, and installed Boot Camp and Vista. I then tested the machine using Vista’s built-in Windows Experience Index, a rating system that goes from 1 to 5.9, with scores above 3.0 generally required for full, quick performance. My iMac scored a 5.0, the best score of any consumer Vista machine I have tested. Obviously, a tricked-out high end Dell or HP box might do as well or better, and a lesser Mac might do worse. But the score was very impressive for a computer that wasn’t designed with Vista in mind.

We have a Sony PC and a 17-inch LCD monitor. Currently, we have a separate old-fashioned TV in the room, with a cable box connected to it. Is there any way to buy a larger LCD monitor and be able to watch TV via the cable box and also use the same screen when we use the computer?

A good approach would be to buy an LCD television that has both the usual connectors for your cable box and a connector, or input, for a personal computer. There are many such models, in various sizes. If you bought such a TV, you would switch between the PC and the cable box by changing inputs on your remote. Just make sure the PC input is compatible with your computer, or that an adapter is available to make it compatible. Many PCs and PC-friendly TVs use the older, common VGA connector, which is an analog input, but others use various newer digital connectors. You can also connect some computers to LCD TVs using standard connectors that aren’t specifically labeled as being for PCs. This is especially true for some Windows Media Center PCs that are designed to work with TVs.

Have you rated any of the Web businesses that assemble personal photos into a book format?

Yes. My colleague Katherine Boehret and I reviewed three contenders in that category in December, and in our judgment, at that time, MyPublisher (www.mypublisher.com) was the best of that group. You can read the column at http://solution.allthingsd.com/20061206. However, the books from Apple, Shutterfly and Blurb are also favorites of many readers.

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.

Write to Walter S. Mossberg at mossberg@wsj.com

Here are a few questions I’ve received recently from people like you, and my answers. I have edited and restated the questions a bit, for readability. This week my mailbox contained questions about moving a 25 gigabyte file from a Mac to a PC, switching the iPhone to horizontal mode, and enlarging font size.

How can I move a 25 gigabyte file from a Mac to a PC?

If the two computers are on the same network, you could simply transfer the file over the network. Or, you could establish an ad hoc network using what’s called a “crossover” network cable, though that might require some technical expertise. You might also try uploading the file from the Mac to one of the online backup-and-storage services and then downloading it to the PC. For instance, a service called MediaMax, at mediamax.com, offers 25 gigabytes of storage free, and claims to work with both Macs and PCs.

For the best combination of simplicity and speed, I suggest you purchase an external USB hard drive, formatted for Windows. The Mac should be able to instantly recognize it, since Macs can read Windows disks and can write to them as well, as long as they use a standard Windows format called FAT. You would just plug the drive into the Mac, copy the file to it, then remove it from the Mac, plug it into the PC and copy the file from the external drive to the PC’s internal hard disk. Update: Due to technical limitations, you can’t copy a file larger than four gigabytes in size to a disk drive formatted using the FAT file system.

A 30-gigabyte or larger Apple iPod can also be used as an external hard disk and thus would do the trick — provided it is formatted for Windows, is set to work in disk mode, and has enough room to hold the file.

Is it possible to switch the iPhone into horizontal mode when typing emails, which would allow for wider spacing on the onscreen keyboard when typing, thus helping to eliminate typing errors?

No. While the iPhone’s Web browser, built-in iPod and photo program can operate in landscape, or horizontal, mode, its email program works only in vertical, or portrait, mode. However, in my daily experience with the iPhone, I have actually found the horizontal version of the keyboard (which appears in the browser) clumsier to use than the narrower vertical version.

My grandmother, age 85, recently stopped our weekly emails and when I asked why, she said the 14″ screen has become difficult to use. I considered a 20″ LCD, but the bigger screens seem to shrink the font, and the Magnifier option under Accessibility isn’t agreeable to her. What other options are there?

I assume from your question that she is running Windows XP. If so, you can enlarge the fonts she uses in several ways, to offset the shrinkage you noted on the higher-resolution monitor. First, in Windows itself, go to the Display control panel, click on the Appearance tab, and in the Font Size menu, select “Extra Large Fonts.”

Most email programs and Web browsers also offer options to enlarge the size of text. For instance, in Outlook Express, go to Tools, then Options, then click on the Read tab and the Fonts button. Change the Font Size setting to “largest.” In the Compose tab, click the “Font Settings” button and select a large font size. While reading an email, she can increase the font size by clicking on the View menu, selecting “Text Size,” and then selecting “Largest.” There is a similar “Text Size” setting in Internet Explorer, under either the View or Page menu, depending on which version she is using.

Finally, if she is reading her email inside Internet Explorer, you might try a very good $25 utility called WebEyes, which enlarges the type on any Web page. I tested it in 2004 and liked it (Read the review). You can get it at www.ionwebeyes.com.

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.

Write to Walter S. Mossberg at mossberg@wsj.com

Corrections & Amplifications:

Due to technical limitations, an individual can’t copy a file larger than four gigabytes in size to a disk drive formatted using the Windows file system called FAT. A previous version of this column incorrectly advised that a 25-gigabyte file could be copied to such a disk drive.

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. This week my mailbox contained questions about buying PCs without Windows Vista, TVs with digital tuners and running the Mac operating system on a Dell.

Even though the new Windows Vista is now being included on most new computers, is it still possible to buy a brand-name PC with Windows XP preinstalled instead?

Microsoft says it is still possible to buy machines preloaded with Windows XP. The company’s deal with computer makers allows them to offer the previous version of the operating system for one year after a new one succeeds it. And you aren’t likely to have the compatibility problems with some hardware and software that currently plague Vista.

However, it is hard to find a brand-name computer priced and configured for average consumers that comes pre-loaded with XP. A cursory check of the online sites for the two biggest PC makers, Dell and Hewlett-Packard, under their “home and home office” categories, shows that all of the computers offered came with various flavors of Vista.

Some models configured for business can still be ordered with XP, so if you really want a brand-name Windows computer that comes with XP, you can order a so-called business machine. But these models may lack some kinds of software and hardware features that mainstream, nontechie consumers might want, and could include some that consumers would find superfluous.

You could also forgo a brand-name model and buy a computer from a local shop that is willing to preinstall XP instead of Vista.

There are some downsides to buying an XP machine. XP lacks some new, tougher security features and the slick built-in search that are included in Vista. Also, if past experience holds, over the typical life of a new computer, more and more hardware and software products will emerge that either will only work with Vista, or will work better with Vista.

We are contemplating buying a new LCD TV. If it has a digital tuner built in do I still have to buy a converter for over-the-air antenna reception in 2009?

No. Any television that has a built-in digital tuner, for receiving digital broadcasts over the air, won’t require a converter in 2009, when all TV stations will be broadcasting only digital programming. The only TV sets that will need a converter will be older sets without built-in digital tuners.

I have read a lot about running Windows on a Mac. Would anything prevent someone from going the other way and running the Mac operating system on a Dell, for example, since Macs and Dells are both based upon Intel processors?

It is theoretically possible, and some hackers have claimed to have done it. But their methods couldn’t be easily replicated by mainstream users, and don’t enable all of the operating system’s features. So, essentially the answer is no. The reason: Apple owns the Mac operating system and doesn’t want it running on non-Apple hardware, so it has erected technical and legal obstacles to stop people from doing so.

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Because of the volume of e-mail I receive, I can’t routinely answer individual questions by e-mail, or consult on individual problems or purchasing decisions. I read all questions I receive and select three each week to answer in the column.

Write to Walter S. Mossberg at mossberg@wsj.com

If you have a question, send it to me at mossberg@wsj.com, and I may select it to be answered here in Mossberg’s Mailbox.

The good news: I just got a laptop. The bad news: I sneezed all over the screen. Yuck! Can you suggest a good way to clean a laptop screen?

Yuck, indeed. It’s best to avoid household cleaners and common rags or cloths or paper products. I advise using a commercial product that includes a liquid cleaning solution and special soft cloths specifically designed for the LCD screens laptops use. These cleaners can also be used on flat-panel TV screens and flat-panel desktop monitors. There are a number of brands, but I’ve had good success with one called Klear Screen, available in stores or at www.klearscreen.com.

The same company makes a product called iKlear, which is for Apple laptops, and a Dell version for Dell laptops, but I assume the products are all basically the same, and this is just a marketing ploy. I don’t believe the screens Apple and Dell use are any different from most others. They all come from a handful of suppliers in Asia.

I recently hooked up to high-speed cable Internet. Up to then I was on AOL and used ZoneAlarm for a firewall and Norton AntiVirus. I would like to have just one security package to worry about. Is this possible?

Yes. Both Norton and Zone Labs make versions that include both a firewall and an antivirus program. But I use the same combination you have been using because I believe ZoneAlarm is a better firewall and Norton is better at catching viruses.

You have indicated that converting Quicken data from Windows to Macintosh can be difficult. I am wondering, just how difficult would it actually be, how would one go about doing it, and whether you think conversion might be any easier in the future after Apple changes to Intel processors?

It’s pretty difficult, partly because the two versions are really entirely different programs with different file formats, and the Mac version has fewer features and supports fewer types of accounts. You can get an idea of how cumbersome the process is, and what kinds of things won’t transfer, at: http://web.intuit.com/support/quicken/2005/win/2159.html. The processor used in the Mac won’t make conversion any easier, unfortunately. That will happen only if and when Intuit invests the money and time to do a truly comparable and fully compatible Mac version of Quicken.

For Quicken users switching to the Mac, I suggest either starting cold turkey with the Mac version, keeping your old Windows machine around just for Quicken, or buying Microsoft’s Virtual PC program. The latter software creates a faux Windows computer inside your Mac where you can run the Windows version of Quicken. This last option is expensive and runs more slowly than Quicken on a real Windows computer, but it does work.

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Because of the volume of e-mail I receive, I can’t routinely answer individual questions by e-mail, or consult on individual problems or purchasing decisions. I read all questions I receive and select three each week to answer in the column.

Write to Walter S. Mossberg at mossberg@wsj.com