Cathy from msn.com asks:

"My Dad always told me that if I changed the oil in my car regularly, it would run forever. What kind of computer maintenance should I do so that it runs for a long time and doesn't crash?"

As long as you're not spilling liquids on the keyboard or using a hammer on your PC for stress relief, physical maintenance is rare. No oil changes are needed.

In the old days it was tricky. Maintenance involved lots of sacrifices to the computer gods, and the stench of sacrificial SIMM memory chips and 386 processors was everywhere. Today, it’s not that bad. While systems can usually run without maintenance, there are a few tools to prevent problems or use as a first step in troubleshooting.

Security Suites

Security is the most important protection you can have on your computer. A PC can have security problems by browsing the Web, or from simply connecting to the Internet. I recommend either "Norton Internet Security Suite" or "McAfee Security Suite", available at any major computer store. Run this full-time to assure protection against viruses, spyware, adware and hackers.

Windows Update

A very important prevention step for Microsoft Windows computers is to get updates from Microsoft. These free updates help protect your PC from Windows stability and security issues. As Microsoft discovers new problems within Windows, they release fixes to the public.

Find this feature at http://windowsupdate.microsoft.com and install the latest "Critical Updates". Then use the "Automatic Updates" program in the Control Panel to receive new fixes automatically. If your PC is running Windows 2000 or XP you can set a time for fixes to be automatically installed. This will prevent crashes and will increase your system's security. Either configure your PC to automatically get and install updates, or manually check for them once a month.

Disk Defragmenter

As I grew up, much of my childhood was spent playing with my toys. The longer I played, the more scattered my room become. Eventually it was a toy-strewn mess, difficult to wade through.

As your computer plays, it gradually makes a mess. A disk defragmenter tool (also called "defrag") cleans up that mess, and puts toys back where they belong. The mess, hidden inside the computer on the hard drive, could slow computer performance. Use Disk Defragmenter as a first step in troubleshooting gradual system slowdowns.

Scandisk

If a file is unreadable or unfixable, the location of the file will be marked so it won't cause any more problems. Running Scandisk (called "chkdsk" in Windows XP) can help with system stability. This is a first step in fixing random system crashes.

Disk Defragmenter and Scandisk are built-in Microsoft Windows programs. If you're running an OS like Mac or Linux, similar tools are available. In Windows, you can find instructions and locations for these commands by opening your Start Menu, clicking "Help" and searching for the name of the tool.