There are several ways to eject a disc from an iMac, including dragging and dropping the icon from the desktop to the trash can and ejecting it with an application. A more advanced solution is to use the Disk Utility feature to eject it.
To eject a disc using the Disk Utility feature:
- Open Disk Utility
- Manually eject the disc
Go to the Applications folder and click on the Utilities folder to access the Disk Utility option.
Go to the drive that is storing the disc, click on the information about the disc while holding command, and select Eject.
If a disc physically won't come out of the hard drive, do not try to repair it. Take it to an Apple store or another expert for repair.