You're not alone. Loud music makes me cry, too.
Seriously, I am sometimes "moved" by Williams' Superman theme, but usually in an uplifting way, not a teary-eyed way. It's a rousing theme. In fact, it's the only thing about the movies I think they got 100% right. And even though I have my doubts about the new movie, I'm glad to hear they want to keep the music.
I still remember reading the end of Kingdom Come Book One; when Superman finally shows up, the movie theme was playing in my head. Pretty cool.
If I'd know that was going to be the high point of the entire story, I might've saved 15 bucks, by the way.