LOl I just replied to your other thread. The link i gave you there for the malware includes a link to back up and restore. Truthfully, I don't think your system will let you do either, but just for grins......... Here
is a good tutorial on how to do a system restore. It includes a video (click on the "click to play" button when you see it lol) that you may or may not want to watch. If you haven't ever created a restore point you may not have the option to do a system restore.