Windows XP includes a system restore utility which is capable of rolling your computer back to a pre-defined point in time, removing all changes made to the system since that point. This can be an extremely useful feature for rescuing your PC from viruses or faulty software problems, but it also eats up a large amount of hard drive space.

By default, system restore reserves a whopping 12% of each logical drive for itself. You can considerably reduce the amount of space system restore uses by cutting back on the number of restore points the utility sets for itself, or you can turn the feature off altogether.

To adjust system restore settings: Right click on 'my computer' and select 'properties.' Choose the 'system restore' tab.

To disable system restore, simply check the 'turn off system restore on all drives' box. Otherwise, highlight a drive and click 'settings.'

Using the slider, you can set how much space on this drive system restore will use for its restore points. Decreasing this number will limit some of your flexibility in restoring your system should it be necessary, but reducing the amount down to about 5% or less should still be safe enough for anyone with a 80GB hard drive. Click ok when you decide on the exact amount, or choose 5% if you are unsure.