From your description of the fault, I would bet on an intermittent electrical contact somewhere in the drivers window control/switches. The logic behind this conclusion is that the windows behave when operated via the door locks, but not via the driver controls. Of course the fault could be elsewhere (e.g. at the other end of the wiring loom, connecting the driver controls), but this is a good place to start.
I am not familiar with the location of these controls/switches in a Galaxy, sometimes it can be a nightmare to access the switch rear, requiring extensive trim removal. This is where the Haynes manual for your car, earns its purchase price.