Yes, I have gone through a few "youtube" videos to do hard reboot but just gave up because I got a new one. Figured someone here knows more than me to reboot it.
Have you taken it to a college IT class and had the students there try to figure out what was wrong with it? Sometimes they need 'projects' to work on to get credit for a class ( this is what Ive been told once) I wouldnt hurt to check it out and its way cheaper that way...just a thought : )