wow, most of you have such brave kids, lol.
we took ryan at about 2.5 and he was petrified. he didn't like the dark, he didn't like the noise, he didn't like the movie. the only thing he did like was the popcorn, hehe.
we're still stuck at winnie the pooh, though he loves the classic cartoons like tom and jerry and roadrunner and such. but finding nemo, shrek and all those are still frightening to him. i guess he's a bit sensitive. he didn't even like the non scary parts in shrek, just donkey and shrek talking set him off.
we've not been back at the movies and he hasn't asked. i'll go with his best friend next time, i'm sure he'll be fine. he IS almost 5 now... at home he just watches short shows like franklin, little bear, penguins of madagascar, etc.
if your son will sit through it and isn't afraid of loud noises or the dark, take him. he'll likely love it! and don't forget the popcorn! :-)