Just one disc, or any disc? You could try re-seating the ODD to see if that does anything. Most likely it's kaput though as Blaise mentioned.
I've had terrible luck with ODD's in laptops - my last laptop had a blu ray ODD that crapped out 3 times in a row just by watching some br movies (only one time each).
Not sure if you could get a replacement - but if you can it would probably be pretty cheap ~$20.