Clean out the temporary files. If you use Firefox click on "Tools" and click on "Clear Private Data".
Step2
Run "Disk Defragmenter" This one can take a while if your computer is really slow. Click -Start -> All Programs -> Accessories -> System Tools -> Disk Defragmenter
Step3
Run "Disk Cleanup" Click -Start -> All Programs -> Accessories -> System Tools -> Disk Cleanup
Tips & Warnings
Remove applications, programs, games, etc..etc... that you no longer use.
Put your photos, videos, and documents on a disk or a thumb drive.
on 8/8/2008
Ive read that it is helpful to perform a checkdisk before defragmenting a drive. It takes a while, but is a necessary function to allow defrag to have maximum effect.
How to fix a slow computer
Novice 
Comments
Nesquibel said
on 8/8/2008 Ive read that it is helpful to perform a checkdisk before defragmenting a drive. It takes a while, but is a necessary function to allow defrag to have maximum effect.