I saw it as a kid. I think the movie started in a book store. Some how a boy ended up in a book or fantasy game like D&D. It was from the 80's or even late 70's. There was dragons, a talking dire wolf, and a knight/fighter that rode the talking wolf. In one scene the older dragon fights a giant troll.

The Flight of Dragons (1982) (http://youtu.be/vn9xV6_yyG0)