I talked my friend into getting the new aluminum 20" iMac which he has had for a few weeks. His son was playing a game on it yesterday when the display just went dark. When he reboots it gets to the blue screen and then the display just goes black. Also there is a disc in the drive which will not eject. He knows the computer itself is working because when he presses the eject key the game asks if he wants to end it and even if he presses it a few times the disc won't eject. Short of taking the machine to the Apple Store are there any trouble shooting methods he can try?