in the search bar, to your right, type 'restore'; click enter (in vista it automatically seaches)
Step3
it will bring up 'Backup and Restore Center'...etc. You need to click : under System: 'create a restore point'
Step4
it will bring up the menu
Step5
find the drive that is your main, usually C:
Step6
Unclick it - it will warn you that you're turning it off.
Step7
Click 'turn system off'
Step8
click 'ok'
Step9
now run in save mode or whatever...
Step10
All steps in one picture.
Tips & Warnings
if you want it back on, follow the steps again, but clicking it back on, instead of off.
having your system restore off, will save space on your hard drive, but also put you at risk for problems, if you decide to roll back later in the future.
system restore is usually only turned off to remove viruses/worms/trojans/etc, so make sure, if you're doing that, turn it back on after you have removed them, so you won't have problems with your computer later on. (restore usually doesn't take up that much space on your hard drive, so it's worth keeping it on)