I've yet to see the movie, How to Train Your Dragon, but it sounds like the dragons don't eat people, raise farm houses with their firey breath or are ridden by lizard men from the Black Ring to hunt down the Divine One.
Just doesn't sound like a movie for me to watch...
Every time there I run into trouble on the road, there is always a dwarf at the bottom of it. Don't they know how to drive above ground?