King Bomi vs. Master Pakku - A small island. King Bomi. He is a brilliant Earth bender. Aang found it hard to defeat him.

Uncle Iroh vs. Toph - On normal, open land with earth and grass. I'm not sure on this one as Iroh could use lightning but as the environment would be best suited to Toph i'd say Toph.

Jet vs. Suki - In a forest with lots of tall trees. Jet.

Longshot vs. Sokka - In a public market with people and obstacles. Sokka.

Azula vs. Ty Lee and Mai - On a fire navy boat on the deck Azula for definate.

Toph vs. King Bomi - In the arena Aang fought Bomi in to free Sokka and Katara. I think it would be a draw.

Katara and Toph vs. Aang - On normal land near a small pond. Anng as he can use 3 bending elements.

Iroh and Zuko vs. Bomi and Toph vs. Master Pakku and Katara vs. Aang - In the enlosed area where the Dai Lee battle took place in Lake Laogai, with the exception of a small pool of water. LOL, that is too hard a question!

• Toph and Bumi vs. the 2 big earthbending mole-like creatures from "Cave of Two Lovers" - In the cave the mole's lived in: I have to go with Toph and Bumi (that's how you spell Bumi) because two giant badger moles don't stand a chance against a blind girl and a mad genius also, because of their smaller size, they'd be able to earthbend faster than the badger moles and have more time to attack and they're just plain awesome earthbenders
  
• Unagi vs. the green serpent from "Serpents Pass" - In a big lake: oh, wow...I'm not sure. they're both giant eel/snake like creaturesOkay, that's a tie. but maybe the unagi because it can spit huge streams of water at you
  
• Mai vs. Ty Lee - Fire navy boat: Ty Lee, definitely. She's too quick and agile for Mai to get a target on her with her weapons. not to mention Ty Lee could paralyze her in an instant. but I'm not saying Mai isn't a good fighter, either.
  
• Yuu Yan archers vs. Dai Lee - In an area with trees: jeez, you're making my brain hurt okay, well maybe the Dai Lee. they're very, very, very elite fighters. but, then again, so are the Yuu Yan archers. I mean, they can "pin a fly to a tree 50 feet away without killing it" as Zhao said. hmmm...well, since they're in an area with trees, then maybe the Yuu Yan archers. they could do an ambush attack. but if they were on the ground, then they wouldn't have enough time to defend themselves against the Dai Li. okay, it's a tie.
  
• Toph and Bomi and Master Pakku and Katara and Iroh and Zuko and Azula and Long Feng vs. Aang in avatar state - In a big open area with lots of earth, and a lake: just to make it easy on myself, I'll say Aang. when he's in the Avatar State he's using the power of??all of??the past avatars. not to mention that his powers
  increase ten fold (if not a hundred) and he can bend elements that he hasn't even started to learn yet. so, yeah...