You are right Kakashi, I also think the Wave Country episodes/chapters were the best, not only because of Haku/Zabuza, but the teamwork between Sasuke and Naruto while first fighting Zabuza and later when they fought Haku in the Ice Mirror thing. And as you said, the story about the Hero of the Wave Country was really touching.

You also mentioned some scenes that you also thought was quite good, and I want to add one, It's when Shino fought Zaku during the Chunin Exam, and we had a chance to see about Zaku's past, I really loved that moment, the music were great and it were really touching/sad.