tri boot - vista, ubuntu, XP

[scarface_jr]

trying to tri boot with vista, ubuntu and XP installed last after it completely crashed on me. previously i had been booting into grub which loaded up my ubuntu and vista bootloader which would then go into another screen that goes to XP and vista. how can i edit grub so that i can boot into XP, vista and ubuntu through grub. by the way i cannot boot into vista at the moment. when i select the vista bootloader option in grub it boots straight into XP. i guess i need to edit the boot.ini files for windows to renable vista but i don't know how to go about it as of yet

thanks

scaface