I've always been a DC Comics kind of guy.
I grew up with them all of my life, Batman The Animated Series, Justice League, Teen Titans, and the Cassandra Cain run of Batgirl ( I miss her.) and collecting trade paperbacks/ keeping up with N52 titles on Comixology, so if we're picking sides,
I'm siding with DC.
Now if its an all out brawl between the characters of both universes, that's more of a tough question. anything could happen in that scenario.
Truth be told? No one cares. Batman's still the better Superhero. However, Batman has beaten Superman on many occasions. If not physically, intellectually. Batman has even mind-raped Martian Manhunter. Just because he hasn't defeated Superman doesn't mean he can't.
Batman's the superior superhero, anyway. A fight between them won't change the obvious.
I think DC's characters are more fleshed out and dynamic, their story lines grittier and more realistic. Their heroes can be extraordinary, but they deal with human problems. I find Marvel has more monsters and magic.
That being said.
Sometimes I like monsters and magic.
So I like them both. Like I say when people ask about Nicholson Joker vs. Ledger Joker, they're going after different things.