I am furiously trying to remember all of my favorites, but it's damn near impossible. So here are just the first few I thought of...
Lord of The Rings: Return of The King
The Riders of Rohan follow Theoden into battle at Minas Tirith.
"Ride now! Ride now! Ride! Ride to ruin and the world's ending!"
The Matrix
The lobby scene. Enough said.
Kill Bill, Vol. 1
The showdown at House of Blue Leaves vs. The Crazy 88.
300
The battle against The Immortals (and pretty much every other battle
)
Saving Private Ryan
The opening sequence at Omaha Beach.
The Patriot
When Benjamin Martin rescues his son in the nearby forest.
"Aim small, miss small."
Hard Boiled
The final showdown at the hospital.
Terminator 2
The hallway shootout at the mall - guns n' roses, baby!
Casino Royale
The opening chase scene in Madagascar.
The Dark Knight
The truck chase scene in the Gotham City tunnels.
Scott Pilgrim vs. The World
Scott vs. Todd, the vegan bass player.
Jurassic Park
The chase scene with the T-rex and the jeep.
Resident Evil: Afterlife
The fight scene with the Axe Man in the showers.
Predators
The Yakuza gangster vs. Predator in the grassy field.
Aliens
Ripley's final showdown with the Queen.
"Get away from her, you B*TCH!"
First Blood
Rambo takes down Sheriff Teasle's team in the forest.
Ong Bak
The foot chase scene in the streets of Bangkok.
Underworld: Rise of The Lycans
Lucian and Sonja battle the vampires in the fortress.
The Professional
Leon vs. the cops in the apartment complex.
Star Wars Episode V: The Empire Strikes Back
HOTH!!
I know I'm missing so many more, but this is what came to me first thing.