i have a new system, built from scratch
specs:
MSI ms-7037m-atx mainboard
P4 478 3.0ghz
Western Digital 200Gb Hard drive
PC400 512mb Ram
LG dvd-+rw/cd-+rw
XP Home Edition original CD

when i try to install XP it checks the system, checks the hard drive, copies files then has to reboot. but when it reboots, it doesnt' continue with the installation. it starts the process all over again (with xp in dvd drive), and if i take the cd out and let it boot from hard drive it says invalid system disk
i've already unhooked all extra peripherals (floppy, modem), i've tried different sticks of ram, i've allowed LBA in Cmos, etc

RAM Test

Western Digital Diagnostic

You can download & create bootable floppies from both these sites.

If there is no problem with your RAM or Hard Drive or XP compatability issues I dont know what to add

Did you run a Set-up program when installing the drive?

Do you get any kind of error message when the CD fails or reboots?