Water spots doesn't matter. But if you are bothered by them use the steel wool and Simple Green Then a top coat of butcher's wax or any wax that does not have silicon in it.

This happen to me when i was working out of my basement from the moisture,first thing i did was to use, a s,o,s pad on it to get read of the rust ,dry it with a hair dryer,then take a spray can of car paint,spray2 or 3 coats,let dry inbetween coats,then put a coat of car wax to it,let dry ,then buff it.Never had any more rust after that.Put the car wax to it whenever it starts to fill tackey.Hope this helps.

I always place a piece of carpet over my saw when not using it. It seems to absorb moister and I never have any rust on my saw table