You shouldn't use XP repair. It is, like the bulk of microsoft's helpful little tools: a mess.
Could you please tell me why you were attempting it in the first place? If you're worried about loosing data then I'd suggest you stop trying XP repair as you will loose things in the process. The best thing you can do in this case is back it up somehow. There are many and varied ways of doing this and I'll detail them if you like.
If you're not concerned about any of the data on your hard disk, then you should do a clean XP install re-formating as you go (though it doesn't appear to be an option to do otherwise in my experience).
Why did you disable USB?