1. The Life and Death of Colonel Blimp (Emeric Pressburger & Michael Powell, 1943)
2. Lawrence of Arabia (David Lean, 1962)
3. La grande illusion / Grand Illusion (Jean Renoir, 1937)
4. All Quiet on the Western Front (Lewis Milestone, 1930)
5. Un long dimanche de fiançailles / A Very Long Engagement (Jean-Pierre Jeunet, 2004)
Blimp is debatable of course, but I'd have trouble coming up with a fifth I felt strongly about otherwise. Joyeux Noël would be next I guess, but I don't remember it all that well.