Eject or boot from a CD or DVD at startup
To eject a disc that won’t pop out if you try to eject it in the Finder (Cmd-E):
- turn on or restart the Mac
- hold down the Eject button on the keyboard (Apple keyboard required, of course).
- select Restart from the Apple menu
- hold down the “C” key as soon as the Mac restarts.
If you don't want to restart, you can open the terminal and enter:
Find the disk number for the CD or DVD (probably disc2, but it is disk3 on my MacBook Pro) and then enter:
disktool -e disk#
where # is the number of the CD or DVD