No I am not.  I shut down the computer and it was fine when I rebooted.  This is not right though.  I did a virus scan and found I have a couple of viruses.  I am going to do some research on how to get rid of them.  One is a trojan - don't know the names of them because I don't have them with me right now.  I may be looking for help on the subject.

Are you by any chance using one of those custom mouse pointers? With some of them, it's difficult to tell what you're pointing at and you may be hitting the close button instead of the minimize button.

Pesky little buggers. They ought to have a virus/trojan forum here. Maybe I'll suggest that.

Good luck!