Wow you never installed XP SP3? - Wow that was THE upgrade that made it really good :).
Whilst I'm fairly sure it will work Win8/X2 on your system I'm not sure the experience will be greatest..
Try running the Windows 8 upgrade wizard see what you get.
Your system is getting pretty old it appears, PC's tend to conk out after 6 to 8 years ... I would consider this a great excuse to upgrade to a brand new Windows 8 PC.... anyway that's what I would do - personal opinion...
Cheers...
Alex