I've had the exact same problem, same burner and I have the most uptodate firmware. I stick a disc in the drive, it takes longer than usual for the yellow light to go away and then nothing--computer cannot even recognize that there is a DVD in the machine. I've tried everything and cannot find a fix. Just like you said its only with certain DVD's, most recent for me were the Seinfeld DVD's and Little Black Book.
Whats weird is if my memory is right, one movie won't work but I've borrowed someone elses copy and it reads. Wish i could find a fix b/c ive been very tempted to buy a new burner.