Problem playing DVD's

For some reason their are certain DVD's (specifically Night At The Museum and Monty Python And the Search For the Holy Grail) that when I try to play they casue the picture to go black with only sporadic flashes of visuals, and everything is black including when I press the PS button. It won't go back to normal until it stops playing the movie. Does anyone know about this problem, has anyone else played those movies without that problem? IS it a malfunction? I have had no other problems with my PS3... help me.

Has anyone else played those movies on their PS3 without problems?

Oh and the sound works with or without the picture, but I take by the lack of posts that no one knows what I'm talking about...Galaxybear

I did answer but you didn't bother to answer the question.