Man.......good match, very close it seems to me. I think water takes it. The way I see it is:
Namor could take or stalemate Dragonman (going by his classic appearance, I haven't read anything with him in it recently), Storm could probably keep Ghost Rider busy, I THINK Captain Planet could keep Firelord busy for a little while, Iceman could stalemate Torch (once again, at least for a while), Thor could probably take Godzilla...after all, he's not exactly new to fighting giant monsters (or giants, for that matter), and Aquaman would stomp on Pyro. After that, Arthur would be able to gang up on any of the others, and the fight would quickly shift in favor of team water. A car thrown at Torch while he's fighting Iceman, and it's five on two.
Not to mention that, since Godzilla is a sea-dweller, there are at least DECENT odds that Arthur could take control of him, or at least shut his mind down.
__________________ "One can do worse than be a swinger of birches..."
-Robert Frost
team 1, captain planet/thor + storm is bad news. captain planet's only problem is the smoke from the flames from team two(though smoke is rare in comics for some reason)and the rain/fog storm or thor can creat can nullify any air pollutants. then cap can do his thing with team two unrestrained.
Team "Water" is simply more powerful. Iceman>Pyro and Storm>Human Torch. Not only that but you gave them Thor and Aquaman. Aquaman can control water on a molecular level and Thor is the God of thunder. Not to mention both have magic and Aquaman has telepathy. Also don't forget that Aquaman and Namor can summon large armies if they're near the water. Captain Planet can manipulate all elements if I remember correctly. Also Thor is a Class 100 strength guy. So are Aquaman and Namor if they are fresh out of the water. Iceman can become pretty strong too if he freezes the mass around him to cause him to grow larger in size.
Only threats are Firelord, Godzilla, and Ghost Rider because of his limited magic.
g.zilla is a massive reason to go with team two, but the CIS/PIS of captain planet.........a radiation borne lizard, he will just put it on his resume with the living smog cloud, giant robots etc