I forgot Avengers, it is also very good.
The last RE movie Retribution wasn't so good; RE:Afterlife was passable and incredible 3D, but unless you like those movies, they probably aren't buys (I own Afterlife, saw it in the theater in 3D also). These movies were clearly designed around 3D.
Pacific Rim is what I use to demo 3D for friends now

How could I forget that one? Pacific Rim is a converted movie and I would normally say skip converted 3D movies, but this one
definitely needs to be watched in 3D.
Finding Nemo 3D was pretty good as well. The Pixar movies aren't "converted" they actually reprocessed them for 3D AFAIK, since they are already all digital. I don't own those in 3D only 2D, but all of them are supposed to be good.
Tron: Legacy has some good 3D scenes, but not the whole film. The rest of it was converted and looks just OK. The good scenes look
really good though
Coraline is stop motion that was shot with a custom camera in 3D. Nightmare Before Christmas and James and the Giant Peach were converted and reviews say not the best examples.
I wanted to pick up The Hobbit 3D, but I will most likely wait for a complete set (and no doubt EEs) once they release all of them.