Some other interesting topics could include the following: Did Odysseus grow and change during his journey? Was Telemachus ready to string Odysseus' Bow? Is Odysseus someone we can learn from or emulate? Good luck!
The easiest essay topics are not always the most interesting. Be careful...if it will be the difference between a lackluster topic that won't take you very long to complete or a great topic that will grab your attention and thrill you every step of the way, I would choose the latter. You will enjoy your task more, and your teacher and class will enjoy your presentation much more than some boring thrown together quickly "easy" topic.
Pick something that interests you and it will basically take care of itself. Be sure to be able to back up what you are saying with quotes and page/line numbers from the text.
One key to a good persuasive speech is to find evidence to support what you're trying to argue for or against. Trying to convince others to believe your opinion will be difficult if you do not have solid evidence from The Odyssey to back up your opinion. Use good quotes from it to support what you're trying to say...make sure those quotes are directly related to your point. Also, consult external sources, as well, if you're allowed to do so; for example, you could consult eNotes study guide that the person above provided for you, or you could consult a reference series like the Gale Reference Series at your local or school library.
One place to start looking for essay topics is the link ("suggested essay topics" here. eNotes has extensive information about The Odyssey, and this link will take you to possible topics for each of the books within the story.
Think about what is interesting to you, personally, and which of these topics could be considered persuasive. Perhaps you should try to persuade your class/teacher that Odysseus remained just as faithful to Penelope as she did to him, despite the relationships he had on his way back to her...after all, he was trying to get back to her, right? Or maybe something about Telemachus and his growth into an adult throughout the course of the story - Did he truly grow up, or was he just waiting for Daddy to come home and save him and his mom?
Just remember that any persuasive speech you do will be more effective if you actually believe what you are trying to persuade others of. And you'll have more fun if the topic is of interest to you. Good luck!