I am thinking about buying an iPhone to replace my Palm Treo. However, I have an extensive contact list and calendar within my Palm software. How would I transfer them to the iPhone?

There are a number of cumbersome methods, but a simple approach would be to sync the Treo to Microsoft Outlook, which can then later be synced to the iPhone.

You say Vista’s graphical interface works best with a separate, or “discrete,” graphics card that has its own memory. You add that some “integrated” graphics systems work fine, too, but they claim some of your main memory. So, if I get an extra 1 GB of main memory, will that compensate for not getting a dedicated video card?

Buying extra memory can help overall performance on systems with minimal standard memory and integrated graphics, which do drain memory. So I’m all for that. But the superiority of discrete graphics cards for Vista goes beyond the fact that they have their own memory. In general, they are more capable than integrated graphics at doing the actual graphics processing. So adding more memory to a system with integrated graphics doesn’t give it all the ability of one with a discrete card.

Is there any program or easy way of transferring email addresses when you change your ISP? Everybody I have talked to says it is a mess.

Although I haven’t tested it in some years, a service called TrueSwitch, at trueswitch.com, is in business to do exactly that. It copies over your address book, and even notifies your contacts of your changed email address, if you wish. When I did test it, it worked fine.

• 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.

My IT department will not turn on the feature in our servers that would allow me to receive corporate email on my iPhone. This has forced me to revert back to my BlackBerry Pearl. Can I transfer my iTunes music to my Pearl?

It depends on what you mean by “iTunes music.” If you mean music you bought from the iTunes store in protected format — which describes most of the store’s catalog — the Pearl can’t play it, unless you go through a laborious multistep process to convert it to unprotected files. If you mean unprotected music that is managed by the iTunes program on your PC, the Pearl can handle it as long as it is in open formats supported by the Pearl, including the MP3 or open AAC formats.

To get these files into your Pearl, simply use the music-transfer software that came with the Pearl to copy the songs from your computer’s hard disk to either the Pearl’s internal memory or to a flash memory card you may have in your Pearl.

I recently purchased a new iMac with the Leopard operating system, and have installed Windows Vista on it as well, using Leopard’s Boot Camp feature, so the Mac can boot into either OS. I would like both of those operating systems to share an external hard drive so I can back up my files. Is it possible to do that?

Yes, provided you follow one of two scenarios. The first would be to format the external drive as a Windows drive, but be careful to use the Windows format called “FAT32,” not the one called NTFS. Out of the box, Macs can see all Windows drives and can read from them all. But they can only save files to Windows drives that use the FAT32 system for organizing files. The downside of this is that the FAT32 system only allows files of up to 4 gigabytes each.

The other scenario would be to use a Mac-formatted external drive, which doesn’t have that limitation. Of course the Mac operating system can handle such drives perfectly, but Windows can’t even see them. However, in your Vista setup, you can install a third-party Windows program called MacDrive 7, which allows Windows to both read from, and write to, Mac-formatted drives. I have tested it successfully with Vista under Boot Camp on an iMac. The $50 program can be downloaded from mediafour.com.

The hard disk on my new Sony VAIO laptop is filling up fast. It is trying to get me to watch a lot of movie trailers. Is all that video stored in my machine somewhere and if so can I dump some of it out?

If your Sony laptop is like mine, not only are the unwanted movie trailers pre-loaded on your hard disk, but so are the entire movies, which Sony actually charges you to watch. In my case, these files took up over 4 gigabytes of precious disk space. This is a particularly outrageous example of what I call “craplets,” unwanted trial software that litters new Windows desktops. You can delete these files and reclaim all that disk space without any harm to your computer.

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

I can’t figure out how to remove a song from my iPhone. How do I do it?

Unlike an iPod, the iPhone has no purely manual-mode option, which would allow you to drag songs on and off of it. However, there are alternative methods.

The simplest approach is to connect your iPhone to your Windows PC or Mac, and allow it to synchronize as usual. Then, select your iPhone in the list at the left edge of the iTunes window in order to bring up the iPhone-settings functions in the large window at the right in iTunes. Click on the Summary tab, and check the option called “Only sync checked items.” This will limit the songs and videos the computer places on the iPhone to those for which you have checked the little box that appears next to their names in iTunes. Next, go into your music library, or into any playlists you have selected for syncing with the phone, and uncheck any songs you no longer want on your iPhone. The next time you perform a sync, these songs will be removed from the phone.

Another method is to place all the songs you want on the iPhone into a single specially designed playlist, or several such playlists. Then, go to the Music tab in the iTunes settings screen and click on “Selected Playlists.” Next, check off only your special iPhone-bound playlists. Once this is done, you can control which songs are, or aren’t, synchronized to the iPhone by adding or removing songs from these playlists. If you remove a song from one of these playlists, it will be deleted from the iPhone the next time you perform a sync.

Neither of these methods will delete the songs from your computer or your iTunes library, or prevent them from playing on your computer.

I have tried to download some pictures recently and use them as wallpaper. I am storing them in my My Pictures folder. But, when I choose to make them my wallpaper, they appear multiple times on my desktop. How can I have a picture cover the whole background on my monitor?

Assuming you are using Windows XP, go to the Display control panel and select Desktop, then find the image in the Background list and select it. Then, under Position on the right, select Center or Stretch. Note, however, that if you have downloaded a small image from the Web, and your monitor has a relatively high resolution, the Center option won’t allow the image to fill much of the screen. The Stretch option, while filling the screen, may result in a grainy and/or distorted image.

I was wondering if you could recommend a good service for automated online backup of a PC running Vista. All the services I have found require the user to manually transfer files to the online site. In my ideal world, I could set up my machine to transfer the files during the evening.

There are two automated online backup services I’ve tested and reviewed, Mozy (mozy.com) and Carbonite (carbonite.com).

Both work on Vista, neither requires manual file transfers, and both are good, though I preferred Mozy when I last tried them in December 2006. However, Carbonite has released a new version I haven’t tried yet, and Mozy has also been updated since then. I don’t think you’d go wrong with either. You can read my review at ptech.allthingsd.com/20061214.

Mozy offers two gigabytes of backups free, and charges $4.95 a month for unlimited backup, though you can save by paying one year or two years in advance. Carbonite offers a 15-day free trial, after which you pay $50 a year for unlimited backup, though you can save if you pay upfront for two years.

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

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