dumbluck, WendellM is on the right track about what to do, but doing it on your own for the first time is tricky. So what I would do is to get a friend who knows computers to help you do it and bug him/her with questions all the time so you can do it by yourself the next time.
WendellM, I think you can backup your windows better if you use a disk imaging program like Ghost instead of zip. It can be found on
www.download.com