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What do you mean a disc is stuck in. What happens when you try to eject it?

Are there any applications accessing the optical drive which would prevent you from ejecting the disc?

Close all the apps and then try to eject it
 
Is the disk in the drive a standard-size disk? (or one of those mini-disks that simply falls into the slot, and you often have to disassemble the drive to get it out?)

As was said, the eject key is a good chance - also reboot while holding your mouse button down.
 
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