I'm glad to see the book coming to the big screen. I am sure the movie will inspire more people to read the book. Will the movie surpass how you imagined the story as you read the book? It is possible and to some it will not. It isn't fair to ask a movie to do that. Your imagination is fluid, always changing while a movie is recorded. You as a reader have your own perspective on the story and the movie creators will have their own too. How true to the book will the movie stay is another question to be answered.
Jennifer Lee had enormous success with her last project Frozen. Disney will have the talent and resources to enable Ms. Lee to create something special. Here is the trailer for Frozen..
I've heard some folks that are disappointed that Disney is making the movie. Perhaps someone else could make it. However, Disney has the ability to turn it into a blockbuster. It is a children's book and Disney has a way with making things special for children. I'll watch it with my daughter. If the movie doesn't go like my interpretation of the book maybe I will re-read the classic. I might not even wait for the movie, I might just read the classic to my daughter!