I know these comments are pretty damn old, but with respect to the music choices in Watchmen: most of them are literally straight out of the comic. In most cases, the text outright quotes the songs roughly where the film uses them. Even the Ride of the Valkyries was mentioned somewhere in the text. I don't blame Snyder for trying to shoehorn in as many pieces Moore mentioned as possible. It's rather unfortunate that some of them didn't fit that well, but that's not necessarily Snyder's fault (although in some cases, he could have picked better versions of them; seriously, Hendrix's "All Along the Watchtower", while great, is kind of overused, and the original "Hallelujah" is not the one I would have picked - although come to think of it, I think that one wasn't mentioned in the text).
As for the Superman film - early days yet. Don't really have enough information to make up my mind.