PS3 Freezing problem

[MDJ87]

So I've spent this rainy sunday watching 2 of the LOTR movies on my PS3. Twice now (once during the first movie and once during the second) the movie suddenly stops playing the sound then it freezes like 10 seconds later. The first time this happened it started playing normally again after about 15-20 seconds but the second time it happened i had to fast forward because it was taking too long. I was thinking it was because the dvd was scratched was had a fingerprint but I looked on both discs and they were in perfect condition. I was just wondering if anyone else has had this problem because I'm starting to think that it's my PS3.