Two suggestions:
1. update the drivers for your DVD/CD drive - R click on My Computer icon on desktop > Properties > Hardware tab > Device Manager button. Check to see if it is listed under DVD/CD-ROM drives and if it has any exclamation mark next to it - this should give you the make and model and you can go to the manufacturer's web site to download the latest drivers. OR you can R click on the device name in Device Manager and choose "Update driver..." and allow the Hardware Update Wizard to search for an updated driver.
If this still does not help:
2. Have a look at
this - you may need to delete upper and/or lower filters in your registry.
Follow the instructions to the letter (scroll down to "Manually delete the registry entries") - don't play with anything else in your registry unless you know what you are doing - registry errors can make a good computer into a good doorstop!
If when you get to where the filters are supposed to be and they aren't there - then you don't have them and that won't be the cause of your problem - don't go looking for them elsewhere in the registry.