I disagree, it really depends on what kind of stories you would like to read. Both companies have different characters and different stories. To me DC's heroes are like gods, people we lookup to save us and give us hope. Marvels characters generally possess more flaws to their character. If you go by movies, Iron Man is selfish and was an alcoholic while Thor was full of pride. Hulk is a monster literally while Black Widow was an assassin. Even Captain America has a major flaw which I have noticed, he is too self righteous. Lucky for him he's been right so far but we're about to see that change in Captain America 3: Civil War.
Most of DC's heroes tend to hold the moral high ground, like Batman and Superman refusing to take a life. This doesn't make them less interesting and makes them different. A lot of DC stories are grand and encompass the entire universe like Jack Kirby's Fourth World Saga and Darkseid war which is an event currently going on. Does this make them better or worse? It really is a matter of opinion and depends on which characters you like more. Both DC and Marvel have very iconic villains. Some examples are The Joker, Lex Luthor and Sinestro for DC and Dr Doom, Magneto and Loki for Marvel. I don't believe that DC would demolish Marvel as they have different characters and different ways of telling stories.
Now in a fight maybe DC could win against Marvel assuming we're talking about the comic book universes. Now in a movie fight Marvel has DC outnumbered as DC only has Man of Steel in their current universe (I'm not counting BvS or Suicide Squad as they release next year). This leaves Superman vs The Avengers, Ant-Man and S.H.I.E.L.D. Now in this battle only the heavy hitters would count so this leaves Thor, the Hulk, Scarlet Witch, maybe Iron Man and War Machine. Iron Man would stand a greater chance if he had Veronica (The Hulkbuster Armour). I included Scarlet Witch as her ability to mess with minds is a powerful tool in this fight as Superman has no feats to show he has resistance toward telepathy. Now none of the Avengers can match Superman physically on their own, not even the Hulk showed feats which Superman showed in Man of Steel. But if those characters work as a team then they stand a greater chance I guess I shouldn't leave out Captain America as he is obviously the leader of the team and can direct the team in combat.