Thor and Hulk could destroy the machines but it would boil down to Zod vs Thor and Hulk (Stark wouldn't have survived). Zod could kill Thor, but the Hulk would only get more and more angry until he broke Zod or ate him or both.
Its really funny how people always overestimate Hulk, just because he gets stronger the angrier he gets. Zods power level is muuuuuuuch higher than anything that Hulk exhibits in the Marvel movies, so even if Hulk can get angrier and stronger, it seems to take a long time for him to do it, since he didn't achieved it yet. That would be enough time for Zod to kill him.
Look at the Zod/Supes fight. After Clark gets a few big hits in, Zod figures out how to distort gravity around him, which enables him to fly. Mere seconds after that he takes Kal-El into outer space.
He would do the same with Hulk, maybe even earlier since he sees that Hulk cannot fly. As soon as Hulk is out of the earths atmosphere, he is toast. He can get as angry as he wants, but he would die.
The real opponent for Zod and the Kryptonians is not Hulk. Faora alone would take outHulk, with her speed and cunning. No, the real problem is Thor!
Thor is not nearly strong enough to beat Zod in a fistfight, but he has Mjolnir and the lightning!
I still think that Zod would kill him, since the damage Zod does to Metropolis shows power on a level much greater than anything in Marvels movies. Hulk and Thor double teaming Zod, however... hat could do the trick, but only if the other Kryptonians are already gone. If Zod still has his soldiers and would actuall use them all, nothing would safe the Avengers. But then again, even Supes couldn't beat Zod and his soldiers at the same time.
Iron Man and the rest would die pretty quick, if they were dumb enough to attack Zod head on. Going by the power of Heat Vision in MoS, Zod could cut Tony inside the armour clean in half in a second.
On the other hand, Supes would have no problems with the Chitauri. Sure, he is one man, while the Avengers were many, but he is also much faster than them. I don't even think that the force field around the portal generator would give him a problem, since Tonys repulsor blast is much weaker than Heat Vision or Supes strength. I really think Kal could punch through it and if not, then he would take the roof off the building and throw it through the portal.
And this is not Marvel hate. Even if I like MoS a lot more, I liked almost all Marvel movies a lot. This is just based on what I think would happen.