Man, you just got me thinking of all the great Vietnam movies out there and which one is the best. There are four obvious contenders: Apocolypse Now, The Deer Hunter, Full Metal Jacket and Platoon. Hard to say but I might put The Deer Hunter as 1 and A.N. as 2. Then round it out with Full Metal Jacket and finally Platoon.
This is a tough one.
1 - Full Metal Jacket - It's just a great movie and I am a huge Kubrick fan.
2 - Apocalypse Now (orig, not the redux) - Duvall, Brando and Martin Sheen. Great movie.
3 - The Deer Hunter - Freaking DeNiro is awesome in this movie.
4 - Platoon - My favorite Dafoe flick.
5 - Forrest Gump - Because We Were Soldiers sucks.