Make sure your pc is not overheating...all the vents clear, processor fan spins freely. processor heat sink not clogged with dust. check the ram
DL the diag tool from your hard drive manufacturer
If it is not those more than likely I would do an inplace install, but thats just me. Inplace install replaces all your system files and leaves your data, also resets your SAM and you will need your cd key and I think it resets WPAEVENTS\ OOBE TIMER HKLM of the reg so you will have to reactivate.
If you do not know what your cd key is here is a tool that will find it
inplace install, not to be confussed with the recovery console, back up critical data just in case, boot from your xp cd , do just like you are installing xp for the first time in the text mode part of install. When the cd finds the current xp partition , do the " R " option , repair.