Both yes and no to this question, as I have yet to see a movie that has been better than the books. However, there is one trilogy that has equaled the books in greatness (in my opinion): The Lord of the Rings. The books are extremely detailed and Middle Earth as a whole is a well developed 'real' world. The movies do amazingly well at capturing the books and giving them life and color, leaving out near to no important details (a remarkable feat, considering the length of the books). The movies are rather long due to this, but well worth it all the same.
Note: this is excluding The Hobbit movies
To kill a mockingbird is probably the most accurate film in regards to the novel. I've read and seen it, and it seems like the director just fired the writers, picked up the book and said "All your lines, blocking, and character development information you need is here". So yeah.
They're different mediums, so obviously there's different factors. Books are based in imagination of the reader, film is based around conveying a narrative to an audience. People that hate on films for not having the imagination variable books have need to stop and understand that it makes no sense. It's like saying paintings aren't as good as songs because paintings don't make sound.
When it comes to adaptation, it's certainly near impossible to capture the feeling of the book, or the tone of the book. And most fans will hate the film no matter what because they love the book so much. But, I've seen some films I liked more than the book.
-No Country for Old Men
It's a short list, but the factors are what matter. While films don't rely on imagination, films have cinematography, and work faster than a book. With most books based on bestsellers, mostly young adult ones, the film sucks. Why? Because most of the time, the book wasn't exactly a masterpiece either. But with these, cinematography, acting, and soundtrack work for the advantage the films have over the books. Are the books bad? Absolutely not, in fact those three books are better than most popular films. But the film adaptations from the books were more enjoyable than the source material.