cganti
If returning the PC is not an option? then:
Go into the bios and set failsafe defaults (these are low performing options that won't stress the hardware)
Next suspect is the memory (XP does tends to turn up weaknesses that 98 wouldn't) so if you have more than one memory module install one at a time and try again.
next would be memory and CPU settings and as you havn't posted your system spec I can only speculate, but these must be set correctly.
Now the CD disk, is it damaged? is it geniune?
If you have more than 1 CDrom then try installing from another drive (possible faulty rom)
Finally, when all else fails, sometimes carrying out a low level format on the hard drive then reinstalling can sometimes have a positive effect.
Martin
Replying helps further our knowledge, without comment leaves us wondering.