ceramic= minimal brake dust. Great for ease of cleaning, less noise, and smoothest.
Semi-metallic= Medium brake dust. Highest resistance to heat. Noisy when warmed up.
Organic= Greatest brake dust. Medium resistance to heat, often noisy.
Almost all performance brake pads are semi-metallic, EBC, Hawk, etc. etc..
If this is for a car that's going to be seeing heavy braking such as track use etc., go with a performance aftermarket pad like listed about. NOT DURALASTS! Pads like that will have brake fad the second time down the track!
If this is a casual commuter car, but you want a decent pad, go with something like a Wagner (O'reilly auto parts, Bumper to Bumper) or (NAPA GOLD?) I beleive that's their highest pad, which is also well suited for an "average" car.
Hope that helps.