I was trying to show a friend how to use email. I turned the computer off and told her to restart and see if she could go to the email program. But, when I turned around she was waiting for the screen to light up. The start button is lit up. I can get no response from anything I have tried. It won't turn off or come fully on. I tried unplugging it as I would my desktop, but of course the laptop had it's own battery supply so unplugging had no effect. Any suggestions?