This subject has come to mind with the magnificent ending of Antonioni's The Passenger; one moment i was admiring the pattern created by the bars, then it started to dawn, a miracle, i'm passing through, free in the air outside. What an uplifting scene that is. 

humans taking flight: 
levitation and flight in Tarkovsky, (albeit briefly in Andrei Rublev), + the liberating power of Faith and the mind (end of Stalker, stammer curing at the beginning of Mirror..). 
The Right Stuff. Flight of imagination in 8 1/2. 

Freedom after imprisonment, physical escape; Papillon taking his chance while Dustin Hoffman stays in more comfortable resignation, and on a higher level, A Man Escaped, the sense of spiritual release after all the tension. Mental attempts at freedom during imprisonment; The Birdman of Alcatraz through his special interest, Hurt's imagination in Kiss of the Spiderwoman (though in both these cases we're always aware the liberation is in fact restricted, and in fact the 2 films are only partially sccessful, imo). 

In Sansho the Bailiff, there's the escape from the slave camp; physical liberation for Zushio, a different, noble liberation for his sister Anju (possibly the most beautiful and poignant moment in films). Leading on to the famous transcendental ending in which a simple camera move takes us from this individual tale to the wider universe beyond 

Or at the end of Rosetta, precisely by restricting their focus to the girl's face we're given a barely perceptible but wonderful sense of hope and compassion, the sense that her confrontation and ordeal with the young man will now be behind her, and with it a sense that she may overcome future struggles, life may slowly improve? 

Dreyer's Gertrud rising above her disappointments and male fickleness, pettiness, ego. 

The overcoming of obstacles. 

Natural beauty, open spaces 

The impossible made possible, suspension of disbelief, fantasy, magic. A Touch of Zen, Crouching Tiger, Orphe.... 

The sheer romantic joy at the end of The Green Ray, with the great affirmative OUI! 

The wondrous destiny of 2001: A Space Odyssey. Those who complained of not understanding the film were missing its point. 

New artistic possibilities opened up within Cinema. Cinema of political liberation (Sembene, Pontecorvo, Loach..), sometimes seeking new forms of expression (Rocha, Godard, Eisenstein..). Cinema itself as a form of escapism... 

and so on; i've just set the ball rolling with the first examples that came to mind. Over to you.