If the drive ejects discs slowly or appears to be struggling, insert and eject a single disc several times.
If the drive does not eject discs using the F12 or eject key on the keyboard try dragging the disc icon to the trash.
If the disc will still not eject holding down the trackpad button during startup should also eject a disc.
Reset the Power Manager (PMU) or System Management Controller (SMC).
ALSO-
1. Restart the computer. If necessary, use the reset/interrupt button.
2. Immediately after the system startup tone, press and hold the Command-Option-O-F key combination. The computer starts up to a text-only screen, indicating that you are in Open Firmware.
3. At the prompt, type: eject cd
4. Press Return.
5. Type: mac-boot
6. Press Return