Paphy, i understand what you are trying to do.
First of all, let me just say that it's 1) illegal and 2) not possible.
It's illegal because with XP Home edition, MS gives you the right to install the OS only on 1 (ONE) PC.
It's not possible for you to just copy the XP files onto your 2nd PC and make it work. You need a ghosting program in order to copy the boot sector from the 1st PC byte for byte. With such a program like Norton Ghost, you can do that. However, the OS will contain information in the registry about the hardware installed in the 1st PC and unless it's the same exact replica of the 2nd PC, it's not going to work.