Here are a few that I find inspiring or otherwise overwhelmingly emotional.

Imitation of Life
Superman: The Movie
The Iron Giant
As Good as it Gets
The Princess Bride
Cinema Paradiso
My Dinner with Andre
Close Encounters
Five Easy Pieces
In the Heat of the Night
The Good, the Bad, and the Ugly
Days of Wine and Roses
The Misfits
The Hustler
La Notte
Spartacus
The Ten Commandments
Bad Day at Black Rock
Brigadoon
Roman Holiday
Casablanca
Gone with the Wind
The Wizard of Oz
Mr. Smith Goes to Washington