I use a wireless optical mouse, and I use the standard WASD keys for most first person shooters, though I can adapt fairly quickly to even the most bizarre keysets [When my left arm was broken, I found a way to play call of duty perfectly entirely with the 10 key.] I don't care for joysticks, but on some games [grand theft auto, oblivion, etc.] I use an xbox 360 controller.
optical mouse, wasd keys, space for duck, mouse2 for jump, q for prone, capslock for alt-fire (the reason some of my chat text is upper case).
My rigs getting old (2.7GHz, 1GB Ram, 6800GT), but I still get along. I have Verizon FioS, but my connection has been very poor since January (communication lost for a few seconds several times a minute - yeah, it gets me killed a lot), but if I can get an updated rig and that blasted FioS connection fixed, I should be in good shape.