1.) The S90 is better in this category because of the larger aperture lens.
2.) The G11 is better for this type but blurry results can happen from two different results: too slow of a shutter speed or not in foucs/tracks slowly. All point and shoots are not great for tracking fast moving objects so you usually have to rely on something called trap focusing. You preset your focus point on an area that you know your subject will pass and when the subject enters that distance then take the shot. It's what I had to do with my dogs when I was shooting point and shoots.
thanks for all your inputs on cams, im finding hard to decide between Canon G11 and Canon S90?
My main priorities are:
1. Good photos in low light,
2. For taking photos of moving objects(kids and sports activities), ... i'm really tired of getting blurry results!! :-((
Will appreciate all kind of inputs,