My SIL actually recommended Shane and I do this before its too late - ie crawling..... You could possibly get away with it while they are still havint good daytime naps, if you wanted to do the daytime thing. Then when they wake you can feed, and get all up about 90-120 mins of quietish time wiiht them?
Although - in my pre-baby days, I would've got pretty annoyed if a baby had cried during a movie I paid $12 + to see.. .. Oh how we change our tunes when babies come along! 8-[