We watched Night at the Museum 2 yesterday afternoon. The movie is funny and informative as well. My son was laughing hard the whole time, good thing the people around us didn't mind (because they were laughing so hard also).
I didn't like the love story part though, it might confuse the kids. Amelia Earhart, the first person to fly solo across the Pacific, fell in love with Larry Daley, played by Ben Stiller, the main character in the movie.
Do watch the movie, you will laugh to your hearts content. Bring your kids, they will surely enjoy it too.