Movie choice question

Ok, due to a lack of babysitters and having a limited budget, my wife and I usually only go to the movies when one of the grandparents is in town. Our next movie night is this weekend. We tend to choose movies that are more enjoyable to watch on the big screen as part of the theater experience, so it's usually spectacle movies (tron, inception, etc). We're on the fence between Thor and X-men: First Class. I've heard good things about both, but that perhaps X-men is the better movie. However, like I said above, what really drives our choice is which one is better on the big screen - in this case, from what I've seen, Thor might be a better decision (plus my wife loves Idris Alba).

So, I ask for advice from those who've seen both films and can help us out. Thoughts?

In 2D, since it's not showing in 3D anywhere right now. (only missed it for the trip through the galaxies in the end credits). Rather enjoyed it - a well-balanced film with humor, action, and character development (somewhat squashed, but it worked). My wife loved it, but thought that Idris Alba "should have played all the gods." I actually was impressed by the Destroyer - it looked somewhat silly to me in previews, but I thought it was a convincing threat. I liked the contrast between the dusty little New Mexico village and Asgard as well. Overall, a fine entry into the Marvel movie line-up. I'd put it below the first Iron Man, the first two Spider-man films, and the first X-men movie, but above just about everything else I've seen.

Thor was the better "big-screen" film. First Class was good too, but I don't think you'd miss as much waiting for it to come out on video.

saw it in 3D, which really didn't add anything to the movie, but the movie was pretty good. I missed Xmen, but plan on seeing Green Lantern this Sunday, then Harry Potter/Capt America next month, and possibly Transformers 3