Just use a wired Xbox 360 controller, it's just plug and play and works a treat.  I most definitely wouldn't be playing HL2 with a pad though, couldn't think of anything worse!  K&M for FPS's/RTS's etc and pads for racing/fighting imo.  That reminds me actually, they are bringing Diablo 3 out on the PS4...  I couldn't imagine using a pad for that type of game surely!?