Ok, here we go...
Battle of Water- Namor vs. Aquaman
Possibly Namor, he can fly, so that definitly is an advantage, then again... i know i so a pic somewhere showing Aquaman beating Superman with his "mystical" hand... but still, i think Namor with his flight, greater strength and electrical powers has an advantage.
Battle of the Archers- Green Arrow vs. Hawkeye
Hawkeye... you got to respect a guy that does not mind wearing pink XD
AND he was trained by THE CAP... so he would definitely beat Green Arrow!
Battle of the Warriors- Superman vs. Gladiator
Superman hands down. Gladiator is ONLY strong as long as his confidence is good enough, so it WILL eventually drop while fighting "The boyscout".
Battle of the Sounds- Banshee vs. Black Canary
Banshee, his powers as more developed than Canary's, he can even fly using them.
Battle of the Cosmics- Thanos vs. Sentry
Hmmm... don't know. Sentry is a Superman knockoff... i must admit i like Thanos better but i trully don't know.
Battle of the Martial Arts- Batman vs. Iron Fist
Batman hands down. Too bad, cause i like them both, but Batman is way better IMHO.
Battle of the Antiheroes- Lobo vs. Punisher
Lobo, no contest. Healing Factor, superhuman strenght, durability, super human intelect (yeah... he is THAT smart), it is even rumored that he may be immortal... against what? Guns? COME ON!
Battle of the Cryokinetics- Killer Frost vs. Iceman
Iceman, omega lvl mutant with WAY more developed powers. No contest
Battle of the Pyrokinetics- Firestar vs. Human Torch
Battle of the Weather Witches- Storm vs. Weather Wizard
I would like to say storm, but i don't know for sure
Team Battle- JLA vs. Avengers
Team Battle- Teen Titans vs. Fantastic Four