The second demo was shooting and is a lot like the old Duck Hunt game. Various objects - ducks, UFOs, targets - float across the screen and you have to blast them out of the sky by aiming with the remote and pulling the trigger underneath.
What was really noticeable when playing this demo was how unnatural the remote felt when using it as a gun. As it's not shaped like a pistol it doesn't have the instinctive feel that you'd get from, say, using a lightgun in an arcade. This is probably why shooting during our Red Steel hands-on (Ubisoft's Wii shooter) didn't feel quite right and is something that developers thinking of making a Wii FPS should take into consideration.