Nah, 38-42 degrees is perfect for lagering with a real lager yeast. You can't get yeast to start at that temp, so start it at about 60-65 and when you've got a good krausen (foam on top), in the 'fridge it goes.

Same with ales, get the yeast started in the 60's, then the ideal ferment temp is 50-55 degrees.

Liberty, so far as how cold - I've cold-lagered here in MO in an unheated shed in the winter. The top 6" of the beer froze solid in the carboy a couple of times, but when it thawed out the airlock started bubbling again. That made some real good beer, too.