Warning, there will be no arty-ass directors here.
These are in no particular order. They're all great.
1. Ridley Scott
Why: Alien, Blade Runner, Black Rain, GI Jane, Gladiator, Black Hawk Down.
2. James Cameron
Why: Terminator, Aliens, Titanic, Avatar.
3. Quentin Tarentino
Why: Reservoir Dogs, Pulp Fiction, Inglorious Basterds.
4. Woo-ping Yuen
Why: First, he's the single best action/stunt choreographer of all time. He has elevated something functional into an art all its own. When I watch Crouching Tiger, Hidden Dragon it's more for Woo-ping than Ang Lee.
And when I watch Charlie's Angels it sure as shit isn't for any contribution McG made.
And as cool as the Matrix is, without Woo-ping's fight choreography it wouldn't be half as awesome.
When he actually takes the entire reins on a movie, you get Drunken Master (Jackie Chan's finest movie) and Iron Monkey, one of the best movies anyone ever made period.
And when his Hands of Shang-Chi movie comes out, it will be the greatest movie ever made.
5. Oliver Stone
Why: Platoon, Wall Street, Talk Radio, JFK, Natural Born Killers, Any Given Sunday (yes, this movie is kind of dumb but god, is it awesome to watch- it's a movie not a fucking english paper).