Surprised I didn't see this thread before. It's a good one. Anyway, my favs in no particular order:
1) Patton - A no brainer really. An amazing performance by George C. Scott. Great screenplay by Frances Ford Coppola. This amazing movie works on so many different levels, though to be fair it is more of a military biography than a war movie. Also, unlike the old PC Gamer wargame critic Bill Trotter, I was not bothered at all by the unauthentic tanks.
2) Tora! Tora! Tora! - A masterpiece of production, editing, and pacing. It was amazing how this movie was filled with tension and anticipation even though the viewer knows what's going to happen.
3) Cross of Iron - Far and away the best thing Peckinpah ever did. The cast, the screenplay, the battles scenes were all incredible. This one in my book is maybe tied for the number one spot with Patton.
4) Paths of Glory - The battle scenes in this old Kubrick film maybe were just sort of OK, but the acting and screenplay were stunning! Kirk Douglas was never better. The best antiwar film ever.
5) Sergei Bondarchuck's War and Peace - The Battle of Borodino in this film has to be seen to be believed. They used about 50,000 Russian troops to stage it. The film I believe was completed about 1970, but after all these years as spectacles go few films can touch it.
6) The Battle of Midway sequence from the War and Remembrance miniseries - Some might disagree with me on this, but truth be told, I liked the Midway sequence in this miniseries better than the Charleton Heston Midway movie. Actor GD Spraudlin was great as Admiral Spruance.
Honorable Mentions:
Kubrick's Full Metal Jacket - Maybe not without its flaws (most notably lead actor Mathew Modine's smugness), but I liked it a lot better than Oliver Stone's Platoon, and the battle of Hue sequence reminded me of the house-to-house fighting in Stalingrad.
Son of the Morning Star - I felt like I was really watching the Little Bighorn campaign in this tv miniseries, and Gary Cole was great as the enigmatic George Armstrong Custer.
Glory - Although the assault on Battery Wagner was great, I was totally blown away by the Battle of Antietam sequence at the beginning of the film.
And a couple of the meh's:
Stalingrad - This should have been the best war movie ever, but it was just sort of OK. Although the couple of battle scenes were tremendous and there were some memorable lines in the screenplay, the movie to my mind reeked of revisionist German post war guilt and angst.
The Red Baron - This one was a huge disappointment. I didn't like the pretty boy actor who played von Richtofen, there was no final dogfight between von Richtofen and Brown, and even the usually sexy Lena Headey managed to look dumpy.
BTW, not sure how Andrei Tarkovsky's 'Solaris' got in this thread, but I have to agree that it is a great film. It's maybe a bit slow-going at times, but anyone with the patience to stick it out to the end will be blown away by the ending.
And Morbii, yes, I agree with you about 'Ran'. Finally saw it last year from Netflix and thought it was fantastic! Thinking about it now almost makes me want to play Shogun: Total War.