Have you seen "Pocahontas"? Have you seen "Dances With Wolves"? Okay, you know the basic story line.
GO SEE IT. IN IMAX.
The special effects are incredible.
The parts I liked...when Jake first woke up in his avatar body. His first contacts with the local beasties. Anything having to do with Grace.
The parts that resonated with me...love against all odds. When Neytiri found her dying father.
The parts that bothered me...the planet as "mother", the New Age emphasis. But if you see it as an opportunity for discussion - good.
I've seen it twice and enjoyed it more the second time around.