Just as odd to not only reject the one who can free you from your torment but also attempt to kill him(if he's the first in thousands of years of waiting right?)

They were wallowing in their ghostness for thousands of years,found the one who could lift their ghostness had arrived, rejected him, sent an avalanche of skulls than changed their minds when he happened to survive.

The film makes it pretty clear that noone can command the ghost army when Legolas shoots an arrow through a ghost. The ghost king revels in the fact that noone can command them except the king of Gondor. He laughs at Aragorn initially but is shocked when his ghost weapon is blocked by what can only be the sword of the King of Gondor right?

I saw a promo of him narrating the Hobbit, it sounded great! I'll check it out one of these days.

This was another question I had but thought I'd get buried if I admitted I never readthe books. How come Sauron's physical form is visible while he's wearing the ring?

Easy there! Some of us had to suffer through this alone for the first few viewings.