Enter the Cmos at initial boot: hit either Del key or F2 which ever your Bios needs to enter the Bios. Go to the boot priorty section and set your Cdrom as the first boot device and the hard drive as the second (you can just reverse the order once XP is correctly installed). Once you have done this hit F10 and save the bios update. You will be prompted to hit any key to boot from the cd. Now, and again I ask, how much memory is installed on that PIII??? You need a minimum of 256mb of ram to make it run ok 512mb would be the best and that is the limit allowed by that older PIII mobo anyway.
Noli Nothis Permittere Te Terere!!
EVGA 680i, Dual EVGA 8800GT'S (650/950), 4 gigs OCZ DDR2 1066, Intel Q9450 at 3.8 Ghz, Koolance Water Cooled, Dual Plextor16x DL DVD+/-RW. Dual WD 250gb 16mb Cache Sata 3.0. 3DMark06 score = 19,168.