Damn.
Step one: Avoid that situation if at all possible.
I would have run the light when I saw him get out of his vehicle. From what information I have, it seems the biker handled things pretty well... The driver almost seemed drunk.
Afterthought: WTF? They guy was wearing flip flops, while trying to start a fight against 2 younger people in the middle of the road by punching a guy wearing a full-faced helmet. Time to start making better choices.