Wow, that's somehow a tough question...
Apart the LOTR movie that I could watch forever, what are my favorite movies?
Well, there's a french movie called
Les Tontons Flingueurs (
imdb) (Mr. Gangster in english) including the greatest stars of the french cinema of the 50's (Bernard Blier, Lino Ventura, Jean Lefebvre, Francis Blanche, etc.)
There's also another french film called
Le Père Noel est une Ordure (
imdb) (with Thierry Lhermitte, Gérard Jugnot, Anémone, Marie Anne Chazel, Christian Clavier, Josiane Balasko... all of them were coming from a company named "Le Splendid"). If you don't know, the dialogues are so well known that you could ask anyone in France about that movie and we could tell you all those dialogues in their entirety.
There's also "
Le Diner de Cons" (
imdb) with Thierry Lhermitte, Francis Huster and Jacques Villeret).
The City of Lost Children (by Jean-Pierre Jeunet) (
imdb)
I could watch again and again those movies. I'm sure I have forgotten a lot of them.