Lord of the Rings, any of them, are what film making is all about.
Not only was it a massive undertaking, we are talking about hundreds of hours of unedited footage taken down to 12 here, shot back to back over many years, but it showed that Hollywood is not the be all and end all of big movies.
The commitment of the director, screenwriter and actors is like nothing I have ever seen, and the dedication to putting on screen one of the worlds most loved books, with as much authenticity as possible could only be achieved through great love for the source material.
LOTR contains tight story telling, beleivable characters (no matter how outlandish), a thrilling, emotionally involving plot, an astonishing technical breakthrough with Gollum and some awesome model and SFX work.
Then of course, the movies redefined what was considered ultimate when released on DVD. The extended versions are better than the theatrical versions and contain the most exhaustive documentaries I have seen. LOTR is without a doubt the most influential trilogy of fantasy movies since Star Wars.
None of these films will ever, EVER (except seemingly, here) make it on to a list of bad films.