alright so i have my primary drive which has xp pro on it...last night i threw in a cheap 15 gig drive on the same ide controler set to slave, and installed vista ultimate. after the computer copieddata to the drive and rebooted the first time for set up, it failed to boot from the slave drive to finish the vista insaletion. couldnt figure it out and really dont care. so i reformatted the slave drive and pulled it out and put the computer back the way it initially was. i boot and the bios asks which version of windows i want to boot from- vista, or another version of windows. i can boot into xp pro no problem, but i cant stop the bios to stop asking which version of windows. i dont understand because it wasnt completly installed, and it was on a complete different drive, which is no longer inside my computer. can some one please help in fixing this...thank you

have a look here

http://support.microsoft.com/kb/289022

Unfortunately editing the boot.ini file won't solve the problem. Vista doesn't use a boot.ini but uses a BCD (Boot Configuration Data) file. You need to install EasyBCD in XP and use it to rewrote the MBR

You can get the program from here

http://neosmart.net/dl.php?id=1

or you can use vistabootpro to restore the MBR.
http://www.vistabootpro.org/

Either should do the trick, I used that to fix my version of XP.