Was afraid something like that would happen. XP is sort of picky. It does things to itself during install time that make it pretty much non portable across computers without tweaking it.
However it looks like MS has encountered it before.
You can use one of the many iso creation utils out there and use a XP CD.
If you installed windows 7 pro or higher you may be able to use the util redk9258 was talking about and use XP mode inside of windows 7. For home edition if you can find it there is a download for XP mode that contains the ISO right from the MS site. Or give XP mode a try and see if that works for what you are trying to do.