I use a controller on my PC for racing games. It's similar to a PS2 controller, and it works great for that.. But any other game, its keyboard all the way. Once you get used to a keyboard, you can do stuff with it that people using a controller couldn't even dream of doing.
Then you're kinda screwed. Seriously, I just play with right handed controls because it takes way too long to go through and remap them on every game I have.