David's right about doing one or the other. I went skiing over xmas/new year with a view to getting some good action shots of my brother. But everytime I went to take a shot I had to stop myself and him from skiing. I didn't ski properly for fear of falling back and damaging my gear.
Plus also by the time he'd gone past me once I had to go past him again and wait for him again.
Take a few hours out from skiing and find a decent spot on the slopes with all your gear, get settled in and shoot from there with the full range of lenses. Higher up the mountain the better, IMO.
A polariser is pretty useful, and converting some shots to black and white is a nice effect.