What characters will die by the time this series ends?
I think the one character I am most sure of, is Iroh. He will die somewhere down the line, and it might be the best thing for Zuko. Iroh even said in "Tales Of Ba Sen Sa" that he was going to die soon. Remember he told his son, I will be reunited with you soon.
Fire Lord Ozai will??die??of course die, as Aang defeats him and brings balence to the world. I think Azula will live, she will be imprissioned as a war criminal. You need a villian to live, to keep hope for the story to continue.
Other characters that might die, are Sokka and Katara's father, Suki, Ty Lee (by Azula). I would not be surprised, but I am not as sure as I am in Iroh and the Fire Lord's faith.