Per descriptions by Google AI for the difference between a score, a theme and a soundtrack:
A "film score" refers to the original instrumental music composed specifically for a movie, usually encompassing the background music that accompanies the entire film, while a "theme" is a distinct musical phrase within the score that represents a specific character, location, or idea, and a "soundtrack" is the compilation of all the music heard in a film, including the score, plus any additional songs or licensed music that might be featured in the movie.
There are some iconic themes out there, like the original Mission Impossible, but they are not scores. The problem sharing a score here, is by definition it could be quite long!
Lord of the Rings. Here the Fellowship theme. Howard Shore
Nolan's Batman Begins - this is the theme, Hans Zimmer
Pirates of the Caribean - another Zimmer, but he is good
The Good The Bad and the Ugly - Ennio Morricone