Here's something a bit different to consider. I know that living in Calgary you see mountains often, but I've found the Alps can be fabulous in winter (and I didn't go there to ski). I managed a couple of nights in Chamonix a few years ago, and taking the tram to the Aiguille du Midi (13,000 feet) on a brilliant sunny day in late December was spectacular. Temp was about +3 C in town and -15 to -20 up top.

On that trip, my son and I drove to Nice to pick up my wife and daugther and then stayed for about a week in Menton -- right on the Italian/French border. Weather around Christmas was sunshine and highs in the low to mid teens (Celsius). You can fly from NCE to both CDG & Orly on EasyJet for not too much. We ended up driving to Nîmes (2-3 hours), in part to see the Pont du Gard as well as sites in town, and took the TGV back to Paris.

We were in Paris between Christmas and New Years and thoroughly enjoyed it. Weather was gray but dry, highs 5 to 10. Museums definitely busy. Tour Eiffel magical all lit up. New Year's Eve should be fun.

To disagree with some of the others, I think you can enjoy the "country" at that time of year, if you are selective. If you want only large cities, then that won't appeal.