Which system are you using? Have you ran a virus scan? Do you have spybot or adaware? What is the problem with your computer? I find that trying to find out what is causing the problem is more useful for the future than just restoring or start again, as the problem could come back.
More info about your computer and the problems you are having will enable more people to try to find a fix. I hope this will be of some help and someone can help you.