Here is a solution for a stuck disc in the CD drive of a Mac Mini when all other posted procedures seem to fail and before you grab a screwdriver, butternife or spatula ...
(This applies to Mac Mini OS X 10.6.2, 2.26 GHz Intel Core Duo)
1. Shut down the Mac Mini
2. Connect a corded USB keyboard to the Mini
3. On the keyboard, press and hold the D key, then press the button to start the Mini (keep pressing the D key until hell freezes over)
4. Eventually, a window appears that says Apple Hardware Test Version 3A150 (you might be asked to select English as your language of choice before you see the test version)
5. Click on the Test button to start the hardware test (the option for the lengthier test is not necessary)
6. Once the test is over, the results will likely say that everything is okay. Choose the option to SHUT DOWN the Mini.
7. Suddenly, the CD will be ejected from the Mini.
This worked for me when all other methods failed. I must give thanks to Kris for helping me find this solution.
Chronos