A lot of this depends on how a director chooses to interpret subtext. I have seen productions where Dedemona is definitely not presented as naive, and to be honest comes across as a bit of flirt. This makes you feel more sorry for Othello. However, equally, as #5 establishes, it is possible to show that Desdemona is "more sinned against than sinning," and then we feel most sorry for her and her youthful naivety.
I disagree that Emilia is the character who deserves sympathy. She is not a naive woman and she contributes to the "mess" by flaunting the handkerchief in front of Iago instead of doing what she should have done...take it immediately to Desdemona. I find Emilia difficult to feel sorry for, really. I sympathize most for Desdemona. She is truly naive.
I agree this should be a discussion board item because I would make an argument for Othello himself. He is clearly insecure given his comments about not having "those soft parts of conversation" and about being "begrimed and black." He even says that he would accept Desdemona having affairs as long as he didn't have to know!!
And this low self-esteem is coming from a background of being a slave and a captive. Even now, as a general, he encounters racism. Iago yells under Brabantio's window that Desdemona is breeding with an animal, and Brabantio instantly knows he's talking about Othello, so people do call him an animal because of his race.
So clearly, he is a damaged soul... someone who can't believe that he is worthy of love and so is very easy to trick. Certainly, Desdemona is a sympathetic character, but I think Othello is just as sympathetic and he suffers even more during the course of the play.
Your question should be on the discussion board for comment and debate. I think Desdemona is the most sympathetic character. She is an innocent victim of one man's envy and another man's jealousy--yes, there is a difference between the two emotions. Both men perform evil deeds at her expense.
I don't think that neither Desdemona nor Othello are very sympathetic.
When Othello asks Des. for the hankerchief, she unknowingly brings up Cassio, thus angering Othello more, and isn't honest with him. She doesn't tell him that she's lost it.
Why is Othello sympathetic? Yes, he's probably the one who suffers the most in the play, but he isn't very caring towards others after he hears that Des. might be cheating on him. He doesn't allow her to explain herself (last scene of the play) and often bursts out in anger. Instead of allowing Roderigo to fully explain himself, he fires him. Sympathetic?
In my opinion, Emilia is the most sympathetic. She comforts Des. when she's upset and is always there for all the characters. Iago treats her like dirt, and still she's kind to him. When Iago confesses what he has done in the end, instead of blaming Othello, she blames Iago. Emilia, even though she is often ignored, is always ready to help someone.