Sounds like your CD/DVD drive is bust.
If the drive opens and closes it should have power, perhaps you should just check the connections on the motherboard and the drive (IDE/SATA).
Then check Device Manager (Right click "My Computer" and select manage, then device manager from the left pane). You can see if there are any problems by locating your CDROM Drive on the right hand side.
From there you can double click or right click then follow your nose to the resolution.
Hope this helps.