PART A.
Important: Make sure the disc is not in use. Quit all applications that are using files on the disc.
1. Place the computer in sleep mode.
2. Press the Media Eject key at the top-right corner of the keyboard.
3. If that doesn't work, drag the disc's icon to the Trash.
4. If that doesn't work, restart the computer, then hold down the mouse button.
To restart, choose Restart from the Apple () menu.
IF A does not work try B
PART B - Use hole near drive with paper clip. Instructions at link.
http://support.apple.com/kb/HT3007?viewlocale=en_US
If B does not work try C
PART C
IF that does not work try this support document but be very careful. You may have to help the disk out manually.
http://support.apple.com/kb/HT2285
Good luck.
Message was edited by: Marcos Duran