It's probably The Empire Strikes Back for me. There is not a track I put up with, or even skip*, to get to a better one. I enjoy every moment of it.
I used to have a tie for second favorite between ALIEN and Star Trek: The Motion Picture, but Star Trek really is the closest of seconds for me.
I recently had to evacuate to Houston from New Orleans for Hurricane Ida and on my drive there and the drive back, one of the things I played was the Empire score (re-edited to match how it was used in the film). I agree, not a track to skip, and I can see the movie unfolding as the music plays, which is a tribute to how many times I've seen the film and how many times I've listened to this music.
I've started writing a little music for microbudget films and more than any other, Goldsmith's score for Chinatown has been the one I return to again and again for inspiration. So it's probably a tie between those two for me.
Across the board favorite is almost impossible to pick for me. I could say the obvious like Empire Strikes Back because it really is a high water mark of film music composition and I've listened to it soooo many times.
If I was stuck on a deserted island, I'd be very happy to have that score to listen to.
Is it my FAVORITE tho?
First Blood and ST:TMP get just as much air time--so does Total Recall to be fair. And Batman, and Something Wicked This Way Comes, and Conan The Barbarian, and Jurassic Park. I could go on.
I just can't pick a favorite...
But, if I was stuck a deserted island, I'd be very happy to have any of those scores to listen to.