Is there a more iconic piece of movie music than the Imperial March (Darth Vader’s Theme)?

I've really made screening movies in my home something of a hobby the past few months. Built a home theater mainly out of components I bought off of Craigslist. (What a steal!) This weekend I had the best movie party yet, and we watched The Empire Strikes Back. A couple days before I had people over, I was thinking about how exciting it was going to be to have a bunch of people in the room with me watching this amazing movie the first time I got to hear this song on my nice sound system.

It got me thinking… Is there a single piece of movie music more iconic than Darth Vader's theme, ever? Don't get me wrong, there's plenty of amazing pieces of movie score I can recall, and I can think of at least several that are comparably famous to this one. But every song that comes to mind, I can't help thinking – yeah, that's a famous song, but Darth Vader's theme is definitely EVEN MORE famous.

I think it's the most famous Star Wars song, even moreso than the title theme. Is there a serious competitor, or is this just clearly the most iconic movie music ever?

EDIT: Of the answers I've received so far, I think "Over the Rainbow" is clearly the most fitting. What a banger. That's definitely in contention.

EDIT 2: I should have mentioned Jaws in my last edit, since that one was on my mind even before I posted. It's clearly in the same "weight class," so to speak. But I think Vader's theme is clearly more iconic even than that.

EDIT 3: Seems like if there's ever going to be an answer somewhat widely agreed upon, it's the theme from Jaws. And although "Over the Rainbow" really swayed me, I think I have to agree with all the commenters here that it's the most worthy competitor.