Snowboarding

I was wondering if there were any more experienced photographers on the sight that could give me some advice on shooting snowboarding pictures. We shoot some on the mountain with various snow and light conditions I'm pretty familiar with shutter speed and exposure levels but would like to know about other techniques. We also do a fair amount of night shoots around the city on different rails and such with limited and low light conditions. I'm searching for the perfect settings.

One of the things I've been trying to do is on a night shoot have the rider clear and focused but blur the background. How would I go about this?

I have a pretty nice Canon so there is tons of settings that I'm not sure how to use.