We normally stay at the Lake Tahoe Vacation Resort since my kiddos love to the pool. It is the kind that you hop in the pool inside and then swim to go outside and the whole thing is heated enough they are comfortable. They love watching the snow fall while they are in the pool.
They are remodeling so no pool so need to find something similar. I posted here because my first choice is south lake Tahoe, but we are skiing and not anywhere particular so could be open to the north side of the lake or even Reno.