Personally, I like the movie better.  It gives me a better look at who Chris really was and his views on life.  However, the book shows how his parents really were better, the movie has a bias point of view with them.  I do think that when we watch movies, it has a greater impact on us because we are visual creatures.  We rely on sight quite a bit and this makes us prefer a version of something if we watch it rather than reading it.