the car should idle higher when it is in cold start.

as far as the car banging around when you shift it into gear while cold, most hondas do that, and any other auto trans that has a full ball style valve body and thick fluid.. the fluid is thick when it cold, and even though you have trans fluid pressure, the fluid sort of moves through the valve body in globs for a few minutes.. it's almost like oil in a pan, how it's all nasty, then when you warm it up, BAM, fully liquid..

hope this eases your mind. no prob. I do recommend switching to a full synthetic. redline D4 or the likes.
synthetic fluid has more ov a tendency to flow well while it's cold regardless of viscosity.