Very Nice event.
I would suggest that you keep the shutter speed no less than 1/400. The pictures are a little soft. Are you taking advatage of the focusing capabilities? The Nikon D100 should have a capability to track down moving subjects even while shooting continuously. It is called Al Servo in Canon, but not sure what term Nikon uses. Make sure you have the proper focusing point selected and that your subject stays in that point
Stay away from the automatic modes. From the looks of the varying shutter speeds, you probobly wont get to far. Shoot at Shutter priority or manual, this will allow you to lock the shutter speed to a constant number and give you the capability to freeze action.
What lens are you using?
Hugh