Ah...I take it this is a Vista machine.
Let's uninstall the drive from Device Manager and have Windows reinstall it with fresh drivers.
First, click the Start orb and type prefetch
in the search box at the bottom of the menu and then click the folder that appears at the top of the menu. You may have to escalate your permissions by accepting the UAC prompts. In the prefetch folder, click "Organize" on the toolbar, and choose "Select All"...press the delete key and accept the deletion. Close the prefetch folder.
Then open Device Manager and expand DVD/CD-ROM drives. Right click on your optical drive and choose "Uninstall"...accept the change. Close Device Manager.
Reboot and see if the drive works properly after Windows reinstalls it.