Its got an eccentric bottom bracket shell. Meaning you adjust the chain tension by rotating the bottom bracket. This means you can have vertical dropouts and run discs without having to worry about disc/pad alignment. I Think it does come with discs though.
Its geared really low as it is a mountain bike. 32x18 with 29'ers would probably give you around 48-50 gear inches. Pretty slow unless you change out the gears. I have a 26" Fisher that I converted to single speed running 32x18 and that gives me 46 gear inches.