No one asked what computer model is in use. Don't buy/use a cleaning disk if you have a slot loading laptop... or a slot loading anything for that matter.
If you have a recent model MacBook you may be suffering what many others are fighting with, and things may have stopped working after a firmware update. I am dealing with the same issue, though it doesn't affect every data disk I insert and nor does it spit out every blank disk (DVD or CD), just some... well... most actually.
If the drive is damaged (and not under warranty) the cost of replacement will be determined mostly by the computer model. A desktop tower (Mac Pro, G4 say) will take significantly less time to deal with than a laptop... A MacBook optical drive replacement could set you back as much as $250 (possibly more) for parts and labour. A tower repair/replacement is not too daunting a task for anyone who knows how to use a screwdriver.
The suggestion regarding System Profiler is the fist step you should follow. And if all is reported as being well and the optical drive is recognised as being there, then it may be that it needs to be replaced.
I would also try the following just so you know you have tried most of the standard repair procedures:
Running fsck in single user mode
Restart (or start up) > hold down Apple key-S
You should then see a
Black screen with white scrolling text > type the following when the scrolling text finishes:
sbin/fsck -fy
NOTE... there is a space between the k and the hyphen...
and then press return
Allow the computer to run though the checks. When the procedure is finished you may receive a message that no repairs were necessary, or that repairs were successful (I cannot remember the exact phrases).
type: reboot and press return key. Mac will restart
Zapping the PRam
Restart (or start up)> hold down Apple key-option-P-R
Keep these keys held down until you hear the start-up chime three times and then release, and allow the Mac to start up.
You may have to reset your computer clock after this procedure.
Repair Permissions
Open Disk Utility, in the Applications > Utilities folder, and choose Help > Disk Utility Help.
This will provide the necessary information on how to proceed. This is, basically:
In Disk Utility, select the computer's hard drive in the list.
Click First Aid.
Click the Repair Disk Permissions button (there is also a Verify Permissions button).
Now... the Apple Help for Disk Utility does not suggest that you repair permissions twice, but I always do this. I want to see a clean bill of health in the Permissions repair summary.
In fact, I never Verify permissions. I go straight for Repair. I don't see the point of checking something that almost always has something to fix.
A PMU reset is not the same on every computer so we will need to know what Mac model is in use.
Good luck
Reagrds
Anthony