Ridiculously bad shot-blocker and a mediocre/bellow average defender. Inapt defending the low post, especially versus bigger centres, good transition defender, acceptable positional help defender - unfortunately he tempers these traits with an awful foul rate.
I'm at loss how can anyone consider Moore a shot-blocker. He's one of the worst 7ft shot-blockers in the entire history of the league. It's amazing how these myths are created: the guy is a 7ft who can run and leap, and plays with lots of energy and hustle, so people just assume he can bock shots and defend, because he fills the stereotype. It doesn't work like that though. He's somewhat of a "fake hustler" (to borrow JVG's expression), because he doesn't translate the effort to an impact on the game.
He's a decent 4th big, good 5th big.