Rapid firing button controllers

Well for a start my controller does not have rapid firing capabilities, it's just an ordinary PC controller that just looks like a PS2 controller.

What I would like to know is there a way to modify the controller options in my settings, or a downloadable file that whould give me rapid firing settings? Peferably I'd like to still use my PS2 look alike controller.

not 100% here but I think xpadder will do this for you. - Some emulators have this ability too.