Black screen with cursor...

I've read most of the responses but have yet to find a solution that would work. We've figured out that leaving a CD in the drive is what caused the screen to go black, but need to know how to fix it. I tried hitting the shift key 5x, heard the beep, but still have a black screen and thus no access to a pop a window. I attempted last good configuration but still a black screen. I started it in Safe Mode but still a black screen with only "Safe Mode" in the bottom corner visible. Please help!