Has anyone come up with a method that allows people to take pictures with a regular digital camera and then download them wirelessly to a computer, and/or perhaps to the Internet?

There have been a few digital cameras with built-in Wi-Fi wireless capability, but the best and simplest method I know is a $100 product called Eye-Fi. This tiny gadget looks and works like a regular, garden-variety SD memory card, but it packs a Wi-Fi transmitter inside. It fits into a standard SD memory-card slot and is compatible with a wide range of camera models from Canon (CAJ), Kodak (EK), Nikon (NINOF.PK) and others.

Coupled with clever software, and a clever Web site, the Eye-Fi card automatically zips your pictures wirelessly to your PC or Mac, and/or to your choice of over 20 online photo-sharing services.

For more information, see www.eye.fi. For a list of compatible cameras, see support.eye.fi/compatibility/. For a full review of the product, see: solution.allthingsd.com/20071121/.

You mentioned last week that SugarSync might be a good solution for backups, so if one computer dies your files still exist on another system. But what if the doomed computer doesn’t actually die but its files are corrupted by malicious software? Do those newly corrupted files overwrite the good copies on your SugarSync network?

They could do so, depending on which folders you had chosen to replicate on your other computers. Automatic-synchronization services like SugarSync have a tough time telling whether changes to a file are deliberate, accidental or the result of some sort of corruption. Though the last is rare, it could look to SugarSync like you had changed the file on purpose.

One way to guard against that is for a service to offer “versioning” — the practice of maintaining multiple past copies of a file. That way, if a change isn’t intentional, you can go back to the prior, pristine version. Sharpcast, the company that makes SugarSync, says it is planning to add versioning to the service, but offers no specific date. In the meantime, one way to back up a file without fear of its being overwritten by a corrupted version is to upload it to SugarSync’s special “Web Archive” folder, whose contents are never automatically updated.

Have you ever reviewed and suggested a media player for connecting to a home theater to play all songs, videos and photos that exist on your home computers?

Yes, I have reviewed several over the years. The one I find simplest and best designed is Apple TV, which, despite its name, can work fine in a household with no other Apple (AAPL) hardware. It costs $229 and is a small, thin, unobtrusive box that fetches music, photos and videos from your home network using either a wired or a wireless connection. It can connect to your TV set or home theater via a variety of analog and digital ports, including component-video, HDMI, and optical and analog audio. It supports high-definition video and works with any computer, Windows or Mac, that has Apple’s free iTunes software installed and running.

Apple TV handles many standard photo, music and video formats, but it is limited to music and video files that iTunes can handle. That excludes copy-protected files in Microsoft’s formats, and certain open Microsoft formats, but includes common files like MP3s. Apple TV also allows you to access YouTube and to purchase music and TV shows from Apple, and rent movies from Apple, without the use of a computer.

• 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.

I listen to opera and other music in languages other than English. Much of this music comes with lyrics and English translations. I like listening on my MP3 player, but I don’t like having to carry around the CD notes to read while I listen. Is there a portable player that would allow me to read the lyrics while I listen?

Yes. The Apple iPods are capable of displaying lyrics while you listen. This capability has been on the standard iPods and on iPod Nanos for a while, and has just been added to the new iPod Touch and to the iPhone. It requires the lyrics to be entered into the song file, either manually or by cutting and pasting.

You enter lyrics using Apple’s companion iTunes software, on either a Windows or a Macintosh computer. To do so, you select the song, then, from the File menu, click on “Get Info.” You then select the tab called “Lyrics,” which brings up an empty window. You can type in the lyrics or first copy them from a Web site (or other source) and then paste them into this window. You then click OK, and, when you synchronize the song with your iPod, the lyrics come with it.

On the standard iPod itself, to view the lyrics while listening, you press the large center button multiple times until the lyrics appear. On the iPod Touch and iPhone, you tap on the image of the album cover while a song is playing. If the song file contains lyrics, they appear.

Does Kodak’s photo software allow one to add titles to the photo — for instance, names of people in group shots?

Yes, as with most photo software, you can add captions or titles to pictures organized inside the Kodak EasyShare software that runs on your computer. You can also add captions to pictures you upload to Kodak’s online photo organizer, which is called Kodak Gallery.

I want to give our five-year-old Dell with Windows XP to a charitable organization. How do I assure myself that all my personal files are safely removed?

One option is to reformat the hard disk, which would leave the computer unusable unless you or the charity bought and installed a copy of Windows, or obtained and installed a free copy of the Linux operating system.

The other option is to leave the operating system and programs intact but “wipe,” or permanently delete, all the personal files that concern you, using a “file wiper” program that overwrites the contents of the file with nonsense data. There are a variety of such programs, including some that are free. To find these, go to download.com and search for “file wipe” or “file wiper.” If you’re willing to spend $30, you might want to use a program I have tested and can recommend called Window Washer, available at webroot.com. It has a “bleaching” function that wipes files, and also has the ability to erase any tracks left by your Web browser.

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 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

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 printing wirelessly from a digital camera, Intel processors, and playing iTunes songs on a Treo.

Is there a way to print wirelessly from a digital camera to a printer?

Yes. A number of digital cameras include Bluetooth, and a few even have Wi-Fi. These wireless technologies allow you to send your pictures to a wireless-equipped printer, over varying distances. In some cases, you can also use this wireless capability to transfer the pictures in the camera to a computer, without the use of cables or the need to remove the memory card.

I am a high-school student and am buying a Dell laptop for use during a semester in Israel. I plan to use the computer only for word processing, watching videos, listening to music, viewing pictures and using the Internet (no gaming whatsoever). Does it matter whether I get Intel’s Core Duo, or Core 2 Duo processors? Also, would you recommend purchasing 1 or 2 gigabytes of memory?

Assuming you are on a budget, I would suggest the Core Duo, since the extra speed and power of the Core 2 Duo won’t make any significant difference in the kinds of tasks you will be performing. However, I would advise spending extra for 2 gigabytes of memory if the computer comes equipped with the new Windows Vista operating system. If you opt for the older Windows XP operating system (assuming it’s available on the model you choose) you will be giving up some degree of security, but you can also get away with just 1 gigabyte of memory.

Is there a way to “authorize” the copy-protected songs I bought from iTunes so they play on a Treo 700wx? Are there any cellphones that can play these songs?

No, you can’t directly play copy-protected songs you have purchased from iTunes on a Treo, because Apple hasn’t licensed the decoding software to Palm, which makes the Treo. The only way to make them playable on your Treo is via a laborious work-around, in which you burn the songs to CDs on your computer, then reimport them as nonprotected MP3 music files and manually input the artist and title data. After that, you could move them to the Treo and play them.

There are only a few cellphones that can directly play copy-protected music purchased from iTunes. One is the new iPhone, which comes out tomorrow from Apple itself, and contains a full-blown iPod that can hold more than 1,000 songs. The others are a handful of Motorola models, which contain a version of iTunes that can hold and play back up to 100 copy-protected songs.

Write to Walter S. Mossberg at mossberg@wsj.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. This week my mailbox contained questions about external modems for a MacBook, resizing photos for email, and using the forthcoming iPhone in Europe.

In your laptop buying guide, you mentioned that the MacBook from Apple lacks both an internal cellphone modem and an external slot in which to insert one. Is there a way to hook up a cellphone modem via a USB port?

Yes, several cellphone carriers offer external modems that plug into USB ports. I haven’t tested these, but have no reason to doubt that they work. However, if you are buying a MacBook, make sure any such modem you buy is Mac-compatible. Both Verizon and Sprint carry a Novatel model that plugs into a USB port and is listed as being compatible with the Mac.

When I email pictures to my sister, she has to scroll up, down, and across to see the whole thing. What can I do to my computer or to hers?

You can make the picture smaller before emailing it. Both Windows and Macintosh computers offer you the option of shrinking the size of photos you email. For instance, in the My Pictures folder in Windows XP, if you select a photo and then choose “Email this file” from the menu at the left, you will be asked if you want to make the picture smaller. On the Mac, in the built-in iPhoto program, when you select a photo and click on the Email icon at the bottom, you are offered a choice of sizes for the picture.

Will the forthcoming Apple iPhone be usable in Europe with a SIM card, and will it be based on a Palm platform or a Microsoft one?

Nothing about any future product can be certain until it is released, but Apple officials have said that the iPhone will be usable in Europe if you insert into it a SIM card from a European carrier. However, it won’t have one of its touted features, “visual voicemail,” which depends upon AT&T, the iPhone’s U.S. carrier.

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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