Sounds like the drive may have a reading laser problem. Was the drive reading discs prior to changing the firmware?
Did a little digging, apparently the product you are using works fine with Samsung drives, so I am going to follow the assumption you have a mechanical issue with the drive. Here is a forum post on a similar issue from the forums sponsored by the product you are using to flash your drive. This post is just proof of concept that the device you are flashing with should be working fine. The fact that some games say "play DVD" shows your drive is at least seeing something is in the drive.