I'm going to be installing Vista as a secondary HDD so I can play my Win only games and iTunes.
If I know Microsoft correctly, they will somehow mess my current set-up up (Ubuntu primary, New Win secondary).
To dual boot these two OS's on two separate HDD's, I should only have to edit the BIOS settings on my computer (HP a6700f, http://www.newegg.com/Product/Product.aspx...-861-_-Product)

I'm 99% certain on this, but better safe then sorry...