My wife's (20" iMac 2.0 w/2GB RAM) machine won't start and I am a little baffled. I can hear the fan and hard drive running, but no chime, nothing on the screen. I unplugged it for a minute or 2 and tried again and it booted. It ran for a little while and then a double panic error was on the screen. I tried to reboot and I was right back where I started. Now I have my startup disk in it and I can't get it out. I've tried the usual remedies and nothing seems to work. Any thoughts/suggestions?