I just returned from a 7 day disney trip at Wilderness Lodge. And I only swam once. It was only in the 60's for the last 4 days of my trip, and a couple of the days were windy, and just wasn't comfortable enough to swim. The weather channel kept predicting it to warm up, but it never happened. Sort of sad to have a courtyard and pool view at Wilderness Lodge, and hardly use the pool. Such is life in January!
The pools are usually open, though January and February are famous months for pool rehabs and closures. And just like Pakey above said, if I knew the weather wouldn't warm up, I would have swam more at the beginning of my trip and taken advantage of the 2 days where the temps did get into the 70's!