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.
At least this is one of the right composers from the era of great film music and one soundtrack close to the top. But the best for me is a tie with Steiner - King Kong, and Korngold - Robin Hood.
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.