Yes, you can use your PS3 controller as a gamepad for PC games.
Yes, you can use your PS3 controller as a gamepad for PC games.
You're trying to play Super Meat Boy with MotioninJoy, but the connection isn't working. You can manually trigger vibrations and LED changes, though it doesn't translate to the game.
MotioninJoy functions properly, but you must reapply the driver each time you use it.
Choose your controller as an Xbox 360 when selecting a gamepad in MotioninJoy. You can assign the buttons precisely similar to PS3, but configure the emulator to X360 so Steam recognizes you're using an Xbox 360 controller for immediate compatibility.