If you think he’s not going to be able to figure out how to drag and drop files in Linux, how can you expect him to run PEbuilder?
Same logic you were using. 
Either way will work, though I misunderstood his original problem.
If you still have your Vista CD that came with that machine, insert it, restart, boot to it like you are going to reinstall Vista, and it should give you the option to repair the OS. Give that shot, provided the machine is indeed finding the drive the OS is on.