First up, i'm not interested in debating semantics of often broadly defined film genres. If you don't believe my nominations fit the bill, then ignore them in your own mind and time.
With that, i'm disappointed that there was not a single mention of my all-time favourite film, Lawrence of Arabia. I just hope most people simply haven't seen it. The epic of all epics, it leaves even Return of the King in it's wake, because all we see is REAL. Sublime cast with a grand lead, working off one of the greatest screenplays, all under heroic direction in the desert. There will never be another movie made like it.
My next pick happens to also be my second favourite film of all-time. I can't believe somebody nominated Apocalypse Now as most overrated war movie. This sounds condescending, but I can only conclude that if you don't like Apocalypse Now, you simply don't have an appreciation of cinema. It's another movie who's likeness we'll never see again. Times have changed too much and studios just do not take risks like that anymore.
The final three places, in no particular order, would be The Lord of the Rings: The Return of the King, Breaker Morant and The Bridge on the River Kwai.