Update: Before you try all of this, you may want to try using WinToFlash, a utility designed to create a bootable Windows flash drive for Windows XP/Vista/7/Server. If this works for you, you can skip ...
I did a search and didn't find any results concerning this problem. I've just built a new system and my Windows 7 disc won't boot, so I'm installing Windows XP so I can then install Windows 7 on top ...