Live action

This is probably general reference, but this might be hard to understand for someone learning English. Even though the phrases are very similar, they mean entirely different things.

1) An action movie is a movie where most of the content involves things like fights, chases, and explosions. This tends to be a very popular type of movie like terminator or die hard.

2) A live action movie is a movie that is performed with real actors filmed with a camera, rather than being animated or being a cartoon. You would use this phrase when trying to point out that a movie is not animated.

The cartoon Scooby Doo has a live-action movie.

Also, the movie Who framed Roger Rabbit? is an animated movie with a bunch of real actors in it. We say that the real people are live-action characters because they are filmed with a camera instead of animated.

When you're talking about TV, "live" means that what they are recording is going straight to your TV. This is not the meaning of live used for live action movie. Live in the phrase "live action" does not mean much of anything, the phrase together is what is important.

No, there is no BETTER term. But if you really require a DIFFERENT word (for undisclosed reasons), you could perhaps re-define the term "Cinéma vérité". If we had some clue about the motivation for needing a different term, we may have a better idea how to respond.