xp sp 1 dualboot with vista

i have an hp pavilion with home premium vista, partitioned the main drive with 40gb for xp, restarted the computer, booted from the xp disc, installed, and then it froze when it got to the restarting computer step. i turned it off and it will boot in xp to the load screen and freeze. I appear to be locked out of Vista until i get xp to work. Was it a problem with the drive partitioning? or is xp sp1 possibly out of date for the hardware im using (pavilion s7700n pc).

any help would be greatly appreciated.