Ok - I am going to try and guide you to the answers. In Greek Myth Lit the Hero has specific traits. Find out what these characteristics are and then you can decide for yourself.
Odysseues does show off traits of the Greek Hero: Brave, Clever, Smart - However it is his Hubris that gets him and his crew into trouble.
Check out these examples from the text and then determine if Odysseus is showing great traits or flawed traits:
1. The Cyclops adventure - do we see both sides of the hero here?
2. Scylla and Charybdis - mmmm more of both possibly?
3. The Sirens - Was there another option for Odyssues?
If you spend any time with the text and understand what traits a Greek Hero showcases then this should not be too difficult.
A three paragraph essay? Intro, body conclusion?
Whether or not Odysseus is a "great" hero is subjective, so pick a side and agrue your point. Don't forget that Odysseues does expose his tragic flaw a number of times.