sir daniel said:
I think that when the power went off, the computer was in the process of copying important files from the CD to your hard drive. So, when you turned it back on, it's trying to boot to a partially installed / corrupt version of Windows Vista 64 bit.
I agree with Sir Daniel's theory.
And I can't agree enough with Royal Crown's Advice. NEVER, EVER, Move a computer while it is powered on.