How do I backup Windows files and folders?

I'm a Mac guy suffering through my foreign wife's need to use Windows. I want to reinstall EVERYTHING from scratch, including a new OS (Leopard) for Mac side and a new Windows because rather than try to figure out what she's done wrong in Windows, it's better IMO to clean everything up and only backup a few files and folders from the old Windows to put on the new Windows. Specifically, I need to save (and then put in the new Windows) a few files and folders from her desktop and then a couple of files such as favorites from Internet Explorer. I've used Time Machine but don't know where to find these files and folders to restore (if in fact I am able to selectively backup and restore individual files and folders or if I must restore the entire Windows). Hoping someone here can help.....

Thanks!