When you spend a reasonable amount of money on your camcorder you can rely on the auto settings to do a good job.
Manual adjustments will give improvements, but for general shooting (is that the right word

) of the children you will be better going with the auto settings. If set manually you will need to reset them every time you use the camera, and if going from inside to out you will need to reset again.
When I have set the camera to manual is is usally for things like plays etc shot under coloured lighting that can sometimes confuse the white balance etc but for general use am more than happy with the auto settings. It just saves so much time and effort!
Mark.