You are running lean. A rough idle and white plugs tells it for sure. An engine needs a much richer mixture to run properly when it is cold. You need to start choking the engine when it is cold. It will cause the engine to draw more fuel and result in a richer mixture. If that does not do the trick, you will probably have to richen the idle mixture. You should adjust the idle mixture anyway, but it should be done when the engine is hot.