you can use work group manager from apple on a local computer (better if it's managed) and turn off burning for the optical drive. You can do this on a per user of the computer basis, or for the whole computer.
Once it's opened and it asks you for a user name and password, click cancel. Then select View Directories from the Server menu. This gets you to your local node. Select the user and admin from there.
Here are screen shots of the prefs that you're looking for.
WGM Optical Options:
WGM Other Media Options:
One cool feature in the other media option is the ability to turn thumb drives and other external storage drives into "read only" storage.
Remember... this is much better in an OpenDirectory managed environment. You can do this as a policy.