The best movie I ever saw? Gee, that is a tough one.
Best I can do is narrow it down to two:
A.) Day Of The Jackal: historical fiction about an assassination attempt on Charles DeGaulle. Based on a novel by Frederick Forsythe. Brilliantly acted and historically faithful. A great story, superbly told.
B.) Breaker Morant. Another example of historical fiction that tells more about the hypocrisy of our leaders in a wartime environment than any other movie I have ever seen. Again, superbly acted. It is based on the Boer War in South Africa but its message transcends all time and cultures. Its a "must see", imho.
Honorable Mention goes to "Das Boot" and The Full Monty.
Oh. Apollo Thirteen. Fabulous flic. And The African Queen. Better than Casablanca, and that's saying something.
Best flic ever? Ain't no such thing!