Shane for its photography, its sexual undertones, its capture in the title character of the iconic lonesome outsider whose skilss were necessary to bring civil society but who cannot live within that society, for its final scene through the eyes of the only innocent in the story.
The Ford Cavalry triology. These films pioneered the use in film of the majesty of the West's real locations and created a mythic world with little connection to the reality of the time.
High Noon for its creation of the 'real-time' film; all the action takes place within the temporal confines of the movie itself, for its powerful contemporary political statement, for its comment on racism (brown, Latina woman a whore and a quitter - white, eastern woman virtuous and brave), for its (then new) portrayal of real fear in the hero.
Naked Spur for its physical look, for its twisted psychology, for its blurring of the line between good and evil and for its redemptive climax.
Hombre....for Elmore Leonards's incredible dialogue (see my tagline for an example).
I’ve never really taken to Shane. “Young guns” was a good movie - certainly the most realistic re-telling of the billy the kid story. And Tombstone too...also for its realism and Val Kilmers brilliant portrayal of Doc Holliday.