my friends computer is just completely raped right now by just about everything. how can i just restart it new and clean. he doesnt care about losing anything. and he just wants to whipe everything so it works again.
Anyway...insert the Windows CD and reinstall. It will ask if you want to format the disk, say yes. That will reinstall the OS. Then just install the drivers and software to get back where your friend should be.
If it had a pre-installed OS, such as you might find on a Dell/Gateway etc. you should see a message during start up regarding hitting a key, like F10 or something to start the recovery process. Just go along with what it says, selecting a "Destructive system recovery" to wipe the disk.