Thanks, guys. Ugh. The computer does act completely normal once I get logged on correctly.
My husband took the battery out last night, but it's still doing it. I'll try again later, though, just to be sure.
I checked the System Restore thing, and it's turned off, so there aren't any restore points.
I went into the user accounts, and there's only mine and a guest one which is turned off, so I don't even know where this temporary one is coming from.
I also ran a full Norton's scan last night, and it found nothing but the normal tracking cookies. Blah.