I'm attempting the same thing except on x64 bit version of XP

From what i've read you need to slipstream SP2 from the SP1 disk, otherwise you will basically wipe everything when you overlap it during the installation.

Don't ask me what a slipstream is though, or how to do it =P I don't know.

 

Normally, when you do a repair install, the Service packs and Chipset drivers need to be put in again after you do the repair because the repair install removes them. The question was asked about slipstreaming, so HERE is an explanation of that process for the both of you.

HERE is even a better link that has the repair install and the slipstreaming issue discussed with a clearer explanation.