In Windows XP:

1. Right click on "My Computer" (This can be found on either your desktop or in your Start menu depending on your computer's settings.)
2. Go to the System Restore tab, and check the box that says "Disable system restore on all drives"
3. Click "OK"

In Windows ME:

1. Right click on "My Computer" (This can be found on either your desktop or in your Start menu depending on your computer's settings.)
2. Go the Performance tab
3. Click "File System"
4. Go to the Troubleshooting tab
5. Check "Disable System Restore"
6. Click "OK"
7. Click "OK" again

In Windows 98, 2000, and before:
These operating systems do not have system restore.