hmm..wonder if your boot order changed; if it looked to a (non-bootable) external drive, that could be something to look at..that's not it, but sometimes it's 'crazy enough to be true'..;)
I would highly recommend backing up everything on C, and thinking about a new HD.

I wish I'd said that.. The Staircase Wit

anahl nathrak uth vas betude doth yel dyenvey..;)