Ben and I watched the Simpsons Movie last night and I must admit, nether one of us was that overly impressed. It was basically like a giant TV episode, but without the clarity and focus of a half an hour show. It was entertaining, but I actually have seen many episodes that are better than the movie!
The overall plot of the movie is that Homer and his rescued pig "Spider-Pig" has caused an environmental disaster by dumping pig poo into Lake Springfield. The poo was the last pollutant to tip it all over the edge. The EPA takes over and puts the city under a dome. The Simpsons manage to escape the city and movie to Alaska, but they are moved to save the day and the town of Springfield.
There were several laugh out loud moments and it was worth seeing once. But as I said above, the episodes you see on TV are actually more entertaining.