Pandora in Classical Mythology was a really beautiful woman, she was the wife of Epimetheus. Zeus had sent her because of punishing Prometheus, the robber of the fire.
One day, Prometheus creates a magical box where to hide all the bad things of humanity. He just wanted to protect the humanity from those bad things. Unfortunately, Pandora opened the box and all the bad things came out, the last and the only good thing that came out was the hope.
Pandora in the movie of Avatar is a land that is also really beautiful, just as Pandora the woman. For the humans is like the box of Pandora because is full of bad things (in fact, they are just fighting for saving their land) but also one good: the money they can win with Pandora’s rocks.