Walking Tall
The New Kids
That movie made me hungry, among other things…
Ender’s Game.
Wild Hogs
High Plains Drifter
The Magnificent Seven. (Seven Samurai)
Shane.
Godzilla’s Revenge.
No. Seriously.
Yeah, I thought about* Seven Samurai* and all of the Seven Samurai remakes. Of course, I thought about The Longest Day and The Damn Busters, too… Don’t know where the “standing up to bullies” and “fighting a battle” line should be.
And speaking of superheroes, Captain America: The First Avenger had him standing up to a bully even before he had superpowers. Plus, of course, he defines the Nazis as just being bullies, too, but that’s not really the same thing.
Bless the beasts and the children
The Color Purple
The Legend of Billie Jean
Almost every coming of age movie has a bully story as a sub plot at least. This feels to me like asking about “Movies where two people fall in love.”
The Longest Yard
Orgasmo
Friday
Meatballs.
The Matrix Reloaded…
500 Agent Smiths is some form of bullying.
In the ending of Back To The Future the altered timeline has Biff getting biffed and put in his place. Of course, that goes back and forth a few times before the series is over.
First one that sprang to mind for me was A Bug’s Life.
Duh! 
Death Wish, and all its sequels.
Pale Rider in spades.