Take good care of your new baby: your PC, that is

If only the some-assembly-required phase of computer ownership ended when you'd figured out what plugs go where, then a new PC would be no harder to set up than a new DVD player — not that manufacturers should take any pride in that accomplishment.

But with most new laptops or desktops, the work doesn't really start until after you first turn it on, thanks to the mix of obsolete or useless programs onboard.

Here's how to go about fixing all that.

Protect the computer: This is the important part — if your computer gets hit by a virus, it won't just be your problem. The virus will probably add friends' e-mail addresses to spammers' mailing lists, then broadcast copies of itself.

Windows XP now comes preset to block the worst online threats. Its firewall program stops Internet break-in attempts, and its automatic updates ensure you're not missing important fixes. Don't stop Windows from doing its job. No matter how long the first round of patches takes — including one entirely new program, Internet Explorer 7 — let it grind its way through.

Then update the other major programs that display or play data off the Web: Adobe's Reader (www.adobe.com/reader/) and Flash Player (www.adobe.com/flashplayer), plus Sun's Java (www.java.com).

If the prospect of installing anything else makes you ill, skip the rest of the download advice here and get the free Google Pack: pack.google.com.

Otherwise, read on: Your new computer probably includes only a month or so of virus protection. Pay for a year's subscription or be ready to switch to another anti-virus tool before the free coverage lapses. (The free AVG is an excellent alternative: free.grisoft.com.) For spyware protection, get Microsoft's free, straightforward Windows Defender (Windows Defender).

If you use a Mac, your risk is far lower, but you still have some work to do. First, turn on your Mac's firewall — inexplicably, Apple still leaves this off. Select System Preferences from the Apple-icon menu at the top left of the screen, click on the Sharing icon, then the Firewall tab, then the Start button.

Then, while you have System Preferences open, select its Software Update icon, then click the checkbox next to "Download important updates in the background." Finally, grab the latest version of the Flash Player at the Adobe address listed above.

Make it useful: Most new computers ship with plenty of extra programs, but you can do better with a few useful additions.

Start with your Web and e-mail programs. Mozilla Firefox is more convenient and safer than IE 7. Firefox's cousin, the Mozilla Thunderbird e-mail program, has an even bigger advantage over Microsoft's aging Outlook Express. Both are free: www.mozilla.com.

For playing music, Microsoft's new Windows Media Player 11 isn't bad — although any new computer will probably ship with only the older, inferior Windows Media Player 10 — but Apple's iTunes (www.apple.com/itunes) is better still. To organize, view and edit digital photos, try Google's free Picasa (www.picasa.com).

If you'd like to listen to Web radio, you'll probably want a copy of RealPlayer (www.real.com).

Mac users should pick up a copy of Firefox — for the few Web pages that won't work in Apple's Safari browser — and RealPlayer. To play Internet audio or video in Microsoft's Windows Media format, visit www.microsoft.com and search for flip4mac to get the free Windows Media Components for QuickTime program.

Once you've added some software, you can get rid of programs you don't need — for instance, trial versions of Microsoft Office or Apple's iWork. In Windows, go to the Start Menu, select Control Panel, click Add or Remove Programs, then select the unwanted program and click Remove. On a Mac, open the Applications folder and drag the program's icon or folder to the trash can.

Back it up: Even if you do everything right, loss, theft or power surges can take out your computer.

You can reduce the odds of those calamities with some inexpensive hardware. If you have a laptop, buy a security cable that can lock the machine down. If you have a desktop, get a surge protector with phone jacks (power surges can travel over phone wires); a basic uninterruptible power supply will also prevent the computer from suffering an abrupt shutdown when the lights flicker.

But you should also back up your data regularly, just in case everything does goes wrong. The easiest backup option is an external hard drive or USB flash drive; the cheapest one is a rewritable CD or DVD.

Then you need a program to automate the backup routine. Many copies of Windows XP include Microsoft's basic Backup program, which will work with an external drive. To run the program, click Start, go to All Programs, then Accessories, then System Tools.

If you use rewritable CDs or DVDs and use only Microsoft's Internet software, the free RightBackup Lite (rightbackup.systweak.com/download.php) comes preset to safeguard all your important files and settings.

Otherwise, try SyncBack Freeware (www.2brightsparks.com/freeware), but remember to tell this program to copy all your data, not just what's in your My Documents folder. Click the folder icon at the end of the Source line, then navigate to the folder inside the C drive's Documents and Settings folder that's either named after you or, if not that, called "Administrator."

Got a Mac? Apple's $100 a year .Mac service includes a backup utility, or you can use the free iBackup (www.grapefruit.ch/iBackup/).

Once you've installed all this software, take a break from adding anything else to the machine. The best way to keep any computer — especially a Windows model — in shape is to be conservative about changing it. Stay current with Microsoft's or Apple's bug fixes, but take your time adding software from other companies. Don't install anything before getting a favorable review of it from a source you trust.

The software industry likes to advertise how security programs stop computer hackers, but most of the time no defense works as effectively — and affordably — as a little skepticism.