Wow! I would recommend it to anyone. I've only seen it in 3D, but I've heard that you won't be disappointed if you don't see it in 3D. The animation is wonderful, and the flying sequences actually take your breath away - not just because it's a whopper of a ride, but because it's actually downright beautiful. No kidding. And I liked the story too, mostly because Hiccup - the boy hero - is so wonderful, his story, his predicament, his expressions, the whole thing.
And we have a little gray cat that has big, green eyes just like the dragon : )
I know this is a kid's movie, but this was one of the best movies I've seen, visually and story-wise, in a long time. Probably since Julie and Julia.
The 3D ticket is pricey, so try to catch a matinee and save a few bucks. Even if you pay full price, though, you won't be disappointed.