Good job to the OP. I have to say I would have done little different if I faced such a situation.
I am even torn about whether or not I agree with the thought of calling 911 during the roadragers antics. While part of me thinks that would be very useful for the 911 operator to be able to hear the roadrager pounding on the window and yelling at the OP, it also would be a distraction. Common sense tells me that in a high stress situation, I should focus on my own self defense first.
But thats just me and my opinion, doubt I'd get 2 cents for it.
"Every man alone is sincere; at the entrance of a second person hypocrisy begins." - Ralph Waldo Emerson
"People demand freedom of speech as a compensation for the freedom of thought which they seldom use." - Soren Kierkegaard