Have a look at
http://apcmag.com/5045/how_to_dual_b...sta_with_linux
General advise tends to be, install Vista first, I shouldn't let it see your Ubuntu disk. Personally I'd rather partition with Linux. If you don't and Vista uses your whole disk, you can get 1/2 of it back, by shrinking the volume later in Vista.
Have a look for saikee's boot info in his signature, there's been lots of boot threads lately. Good luck!