I'm running Windows 7 Ultimate, and I'd like to use Windows Virtual PC to run both XP-Mode and other VHDs I've created. Is it possible to do both?
Windows virtual PC, the next version above Microsoft Virtual PC 2007, supports other Windows operating systems besides XP. One can extrapolate that other operating systems could be ran under Microsoft Virtual PC, but they wouldn't be "supported". Some information about the support and performance of Linux in Microsoft Virtual PC is included in the Wikipedia Article.