Are you talking about surround cinemas like the imax theaters which require special film and special screens? Or are you referring to 3-D versions of 2-D movies? I saw quite a few family-friendly (of course) movies in both 2-D and 3-D versions (Disney's Up is a good example) and enjoyed both viewings. The 3D movie tickets are a bit more expensive as they provide you with 3D glasses which are essential for 3D viewing. They can be shown on regulation screens.

There was also a story on PRI (public radio international) about how the 3D movies were supposed to be better for your eyes, but I only caught part of that, so I can't explain why.