Well, mama decided that it was going to the store before I could look at it. After being unplugged and rebooted there, it came right up. They coudln't find any reason why it did that, and hypothesized that it was going bad. I've moved all the vital stuff out of it onto the primary C drive just in case. I'm tempted to pull it, install it back into the old computer, and then wipe that one clean with a restore disk, and use it as a spare game 'puter networked into this one.