How can completely reset my laptop?

I have a ThinkPad with Windows 7. I think it has a virus because when I plug in the power cord it automatically crashes and when I attempt to burn something it won't detect the burner-- even after I installed a second external burner. So, I want completely reset it to it's state of when I took it out of the package. I hope this will solve my problem. So, how do I do this? Or if you know this won't work and have other suggestions, please post any ideas. Thank you!