Unknown icon on a Canon G9

this shows up to tell you image stabilization is on. usually it happens when the shutter speed is on the slow side because of low light or when you zoom. if the hand is red, it may mean that you have a very slow shutter speed and will likely get a blurry image unless you are photographing a still subject and using a tripod.

This is the anti-shake image stabilization (IS) icon. It just means that the camera will assist you in taking crisper shots even if your hands are not super steady.
To turn it off, press the "Menu" button and then scroll down the first tab until you get to "IS". Then, use the directional control buttons to choose whether it is always on, sometimes, or off.