I have not read the books. But I watched the movie. Bought the DVD for movie and the Dragons: Defenders of Berk part 1 and loving it.
It is about friendship with humans and dragons. There are a lot of adventures and it is a lot of fun just thinking about flying on dragon's back. It is also about a physical challenged boy with his physical challenged dragon.
Losing a leg, and having a prosthetic leg, riding on a dragon with prosthetic tail wing.
This is encouraging.
Now, here is the website I found that link to the books.
Highly recommended for children and adults.
It is also about how children acting toward adults expectation. The father of Hiccup is strong, yet, Hiccup is skinny and not so tall. How do he fit into the world after losing one leg in his last adventure? I like the part about using tools, studying dragons and observing behaviors. The whole attitude over something as scary as dragons is really inspiration.