Well, maluminse, another way to look at it is that cylinder #4 is running mean and clean, and it's cylinders #1, #2, and #3 that are screwed up...!
I agree that it is immediately obvious when a 4-cylinder engine is running on only 3 cylinders, both in terms of idle roughness as well as driveability. The best test that I know is to remove one spark plug wire at a time. When you remove a plug wire and the engine performance doesn't change, that cylinder is not pulling its weight. Now, that's not to say that even if all 4 cylinders are firing, each of them is 1/4 of the total power output. Some cylinders might not be performing up to their colleagues because of low compression, oil fouling, too hot/cold, bad spark plug/wires, wrong air/fuel mixture, etc.
My guess is that, since your car drove fine, all 4 cylinders are firing. There could be many reasons why cylinder #4 appears cleaner than all the others. One common reason is that cylinder #4 is running hotter and burns off all the carbon deposits, due to the fact that this cylinder is last in line to receive "cool" coolant that has just came from the radiator. So, to add to your list of things to check: coolant and radiator performance.
To answer your question: If you are sitting in the drivers seat and facing forward, the engine spins counterclockwise.
-Bryan