A: You will begin to see more touch-screen laptops after Oct. 22, when Windows 7 comes out, because that new operating system has optional fingertip touch-screen navigation built in. In addition, many of the major Windows PC makers are adding their own touch-navigation systems to newer models.

However, I’d offer two caveats. First, not every touch screen will be capable of performing all the multitouch actions and gestures Windows 7 will offer. Some are more limited in their capabilities.

Second, the hardware makers will likely be cautious at first about adding fully capable touch screens to all or most of their laptops.

This is partly because these screens can add significant cost in a price-conscious market, and partly because nobody is certain how popular touch-screen navigation will be on laptops as opposed to, say, on all-in-one desktops where reaching for the screen is more obvious and natural.

I have an Apple iMac, and an Apple iPhone with around 122 apps. My question is, why don’t these iPhone apps work on the iMac? Both units use the same operating system, so why not?

A: While the iPhone and the iMac each use a version of the same operating system, Apple’s OS X, they aren’t the same operating systems. The version on the iPhone is stripped down, and has been modified to support an entirely different user interface, navigation system and set of hardware capabilities.

So there are two separate collections of apps, or programs, that run on the two platforms.

I am currently running Windows Vista Ultimate on my Dell PC. I have regretted it ever since I upgraded from XP because of its terribly slow performance. I have heard good things about Windows 7 but I am afraid I will have to buy the more expensive Ultimate upgrade (which I don’t really need) instead of an upgrade to Home Premium or Professional. Is that true?

A: According to Microsoft, owners of Vista Ultimate can only perform an “in-place upgrade” to Windows 7 Ultimate, not to lesser versions. An “in-place upgrade” is the type most people think of, the type where all your programs and files and settings are preserved just as they were, but you emerge with the new operating system.

Even then, you must be careful to buy the edition of Ultimate that matches the type of architecture your machine possesses, either 32-bit or 64-bit.

However, you can downgrade to the Home Premium or Professional versions of Windows 7, if you are willing to do a lot more work, by opting for what Microsoft calls a “custom installation,” something commonly known as a “clean install.” This typically means, first, backing up all your files and settings to an external hard disk, then allowing the Windows 7 installation disk to wipe your hard disk clean before installing your preferred version of Windows 7.

You would then copy back all your files. But you cannot do the same with your programs. For these, you would have to reinstall every one, from their original disks or downloaded installation files, and then download and re-install all the patches and program upgrades that have been issued by their makers since you acquired them.

You can find Mossberg’s Mailbox, and my other columns, online for free at the All Things Digital Web site,

http://walt.allthingsd.com.

To my mind, this is more a parenting issue than a technology one. The easiest method would be to join Facebook yourself and become one of your teens’ ”friends” on each account they have. That might not sit well with your kids, but if you’re willing to be tough, you could make that a condition of their being on Facebook. You could also insist they use the network’s extensive privacy controls to guard their detailed information and activities from strangers.

There is a paid service called YouDiligence that claims it will notify you if certain words appear on a child’s Facebook page. But it requires that you be one of your child’s Facebook friends, so it is mainly a time-saver. Also, because it focuses on words, it doesn’t flag photos or other Facebook activity.

Another paid service, called imView, automatically takes pictures of the screen of the PC your child uses, at intervals you select, and allows you to view these screen shots at your leisure, from any Internet-connected PC. Its maker touts this as a way to monitor Facebook activity. I haven’t tested either of these two services.

I want to transfer my Mini DV taped videos from my video camera to my Mac. But my new MacBook has no Firewire port, which is the only port my camera includes — only USB ports. Am I stuck?

Maybe not. One option would be to see if you can borrow a Mac or Windows PC that does have a Firewire port, convert the videos to digital files on that borrowed machine, and then transfer the resulting files to your new Mac using an external hard disk or flash drive. Obviously, you wouldn’t want to have to do this often.

Another option: A company called Pixela (pixela-1.com) claims to have a Firewire-to-USB cable meant for exactly your situation. It is for Windows only, but might well work if you installed and ran Windows on your Mac. However, a glance at the company’s Web site shows it is out of the version of the cable that works with the North American, as opposed to European, video standard. If you are in North America, you might check with the company to see if and when the correct version will be available. One important caution: I haven’t tested it, so don’t know how well it works.

My computer crashed last fall, and I lost thousands of iTunes songs. I would like to copy all the songs to my new computer from my iPod, which still contains them. However, iTunes allows only purchased songs to be returned. Is there software that would help me?

Yes. There are several utility programs designed to copy the contents of an iPod back to a Windows or Mac computer. The one I usually recommend, because I have found it works well, is called Music Rescue. It costs 10 British pounds, or about $15 at current exchange rates. It can be purchased at kennettnet.co.uk.

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 want to purchase an e-reader. Currently I use my Palm Tungsten, but the screen is rather small for reading books. I purchased the Amazon Kindle for my niece but I do not like the design of it. Are there any other e-readers on the market that have a full keyboard and can connect to the Internet?

A: There may be some obscure models that do, but the main competitor to the Kindle, Sony’s Reader, lacks a direct connection to the Internet. You have to purchase titles on a computer and then move them to the device. The Reader does have a keyboard, but it’s virtual, not physical.

I’m considering the new 13″ aluminum-body MacBook. I’m a nontech guy doing routine computing tasks. I own an iMac and I’m ready to add a laptop. The only downside to the new MacBook seems to be the absence of a FireWire port. Is that a deal killer?

I don’t believe so. At one time, FireWire (also called 1394 or iLink on some computers and peripheral devices) was much faster than USB, but now the two are about the same speed. At one time, plugging most camcorders, or many external hard disks, required FireWire. Now both types of devices typically use USB or offer both types of ports.

If you are a professional photographer, videographer or musician with a heavy investment in USB peripheral devices, then the lack of a FireWire port may make the new MacBook a non-starter. But for an average user, unless you have invested in FireWire-only peripherals, I don’t think its absence would matter at all. Besides, you still have your iMac, which includes FireWire.

• 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.