Mac OS X 10.6: If the disc burning options are dimmed or unavailable
If you want to burn a CD or DVD but the Burn Disc command in the File menu is dimmed or unavailable, you may not be authorized to burn discs or your optical drive may be unable to burn them.
Try these suggestions:
You may not have permission to burn discs on this computer. If you are the computer’s administrator, make sure you’re logged in with an administrator name and password. Otherwise, check with the computer’s administrator.
Your optical drive may not be able to burn the type of disc you’re using. Open System Profiler (in the Utilities folder in the Applications folder) to find out.