Vista Boot CD wont BOOT

I built this computer at the end of last summer and ordered vista home premium builders edition with it...i ended up going back to xp so i could run Avid however, I have 2 hard drives and I want to be able to take advantage of DX10 for some games and would like to be able to dual boot into vista. So I backed up all my files and tried to load vista on my other harddrive. However I can't seem to boot from the Vista CD. I have tried everything I can in bios however, everytime it just says boot from CD...and just sits there for a minute and finally stops trying. I have CDRom as the first boot device and the hard drive I want to install it on as the second. I've tried disabling the xp drive in bios. I've tried disconnecting it physically. I even went into xp and formatted the will be vista drive in there. However the CD will not boot. I've only used it once and since then its been in its packaging. the CD looks perfect with no scratches. I tried my XP cd for kicks and it works fine to boot. I dont know if becuase it is a builders edition supposed to be used on only new computers if they have something tricky that prevents it from booting. Either way this is really frustrating and im not sure what to do.

Your CD / DVD sounds F**k'd try it in another machine if its still doing it there, get a new copy!!!

go to your bios and set you primary boot configuration to be the cd/dvd drive