The system will automatically mount your CD/DVD and start a file browser on them. To eject a CD/DVD, you may press the right mouse button on the CD/DVD icon on your desktop and select the eject option. Alternatively, you can type in the command eject in a console to have the same effect. Remember that as long as you are in the CD folder, the device cannot be ejected. Make sure that you don't have a file browser open in the directory or its subdirectorieson the CD or DVD and then try again to eject.