under the Apple Menu (top left corner of the screen) find the Superdrive and confirm that it is actually a superdrive and not a combo unit.
Even so, it should still burn CD's
Do you have any other CD burning program on your machine, Toast perhaps?
Are you absolutely sure that there is nothing on those CD's.
Once you burn a CD from the Finder, the disk is finalised and cannot be used again. ie, it does not do sessions without some tweaking.
Put one in, double click it when it mounts and see if there is anything on the disk.
Just a thought.
P
I am a new iMac user who is trying to write to a CD for the first time. I have tried inserting two different brands of new CD-R into my SuperDrive. Each time, the Disk Utility tells me that the disk is read-only, and that the disk has zero capacity. The icon of the CD appears on the desktop, but if I try to move files to it, I get the icon of a circle with a line through it to indicate the the operation is not allowed. I would not be surprised to find out that I am making some simple newbie mistake. Anyone have any ideas?

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