Um, that was El Dorado; Rio Bravo was the one with Dean Martin, Walter Brennan, Angie Dickinson and Rick Nelson. Both great fun, but Bravo’s better.
One of the best western directors ever was Anthony Mann, who had a remarkable streak of films in the 50s: Winchester '53, The Far Country, Bend of the River, The Man from Laramie, The Naked Spur, and Man of the West, all better than most of the non-Peckinpah/Ford/Hawks films listed above.
Other greats gone unmentioned: Jarmusch’s Dead Man, Sjostrom’s The Wind, Altman’s McCabe & Mrs. Miller, Walsh’s Pursued, and Boetticher’s Comanche Station, Ride Lonesome, Buchanan Rides Alone, The Tall T, and Seven Men from Now
The Good, The Bad, and The Ugly.
Unforgiven.
She Wore a Yellow Ribbon.
High Noon.
Once Upon a Time in the West.
Magnificent Seven.
Gotta second Crunchy’s comment here, Seven Samurai is awesome. Also if you can find it you should watch Yojimbo, the original Fist Full of Dollars.
I’ve always been very fond of The Man Who Shot Liberty Valance. Not only does it boast terrific performances from Jimmy Stewart, John Wayne and Lee Marvin, it also deconstructs the western myth 30 years before Unforgiven - and, IMHO, just as well.
It is about a possee that debates over whether or not the lynch some people they believe guilty of murder. I won’t give away the ending but it was pretty good.
A couple of very good ones not mentioned: Hombre, a real fave of mine… The Cowboys, Wayne’s best (IMHO) and a devilishly great job by bruce Dern (“Now, old friend,… I’ll have the gun…”) #1 though, Tombstone
and I also liked Chato’s Land.
The Man Who Shot Liberty Valence
True Grit
The Shootist
High Plains Drifter
Pale Rider
And, let me go on record here as saying I hated Unforgiven. It is, in my other than humble opinion, not just a terrible western, buta terrible film. The performances were stilted. The dialogue was forced (even the much ballyhooed "We’ve all got it comin’, kid) and the politically correct cliches were so hamfisted I saw them coming a mile away. I’ve watched this thing 4 times, trying to see the appeal, and it just doesn’t work for me.
I’m not really a big fan of Westerns, but here are the top three that I’ve loved:
#1–Fistful of Dollars #2–Tombstone (Kilmer did a fantastic job as Doc) #3–Pale Rider (I can’t tell you how many times we quoted the “Nothing like a nice piece of hickory” line in arnis class–usually right after getting clobbered with a nice piece of hickory).