dual boot vista xp

Hi
I have tryed to dualboot vista and xp,created a partition from the vista dvd (i have followed a different tutorial from apcmagazines.com) reebooted from xp cd installing xp in the new partition,then xp reebooted the pc and at the GUI screen it stops before finishing to load anything, after it finds the hard drive it just doesn't do anything and.
please if anyone can help me out in understanding what went wrong and have a possible solution it would be very helpfull.
thanx