Go into bios, put cd rom as first boot, save and exit, put in the xp cd, and it would boot from there. Then it is pretty much click next.
Looking at that system though, I have had alot of trouble trying to get xp working on a older system, more than it is worth tbh, as I couldn't stand the speed of it, but you have a good bit of ram to help it.
If that doesn't work than, Get a 98 boot up disk, (hopefully it would already have A as first boot) type in, with windows 98:
Take out the 98 disk, put in XP
Cisco CCNA, Comptia A+, 1/3 through CCNP