EVERYONE FEAR NOT, FOR I HAVE ARRIVED!
Lel
Well, for a PS2 controller, you need a ps2-usb or a ps2-ps3 converter (both are the same) obviously. I think these converters will most probably be plug-and-play compatible so you don't need to look for drivers. If you have a ps2-x360 converter that would be the ideal solution, since x360 controllers have native support on Windows.
To enhance the experience with a PS2 controller (fix dumb stuff like diagonal inputs not working), use a tiny program called x360ce, which is an xbox360 controller emulator. Google it and see how to use it. It's great.
For a PS3 controller, the best thing to use is Motioninjoy. I think that's the best Dualshock 3 driver out there. Install the driver and you're good to go. I think you can also use x360ce with this to make the game think you are using an x360 pad and you don't have to remap/configure any buttons in-game.
Again, if you have a ps3-x360 converter, it would be the ideal solution. Just plug it in and you're good to go.