Below are a variety of shots, some of which are easily accessible with pullout parking, and some that require a little more effort by hiking in the snow or snowshoeing. If you're heading to Banff in winter, just make sure you're prepared. When I boarded my plane from Virginia it was 55° F, when I landed in Calgary, it was 10 below! Plenty of layers, down, and movement. When you stop for a photo, make sure you understand your gear well enough to move efficiently. Your body will begin to cool down immediately, and you need to take enough time to get a good shot, but not waste time to the point that your body (particularly your hands as a photographer) gets too cold and you lose motivation.
First stop, Lake Minnewanka (easily accessible):
The following three are from Johnson Lake, easily accessible but you'll need to hike a little bit to get that perfect shot:
The next four are from Boom Lake, this is a gorgeous backcountry hike/snowshoe. It's a fairly easy hike in the summer, but the difficulty is slightly higher in the winter. Still very doable, just allow a little extra time as your pace in winter will be a little slower:
Lake Louise, easily accessible:
Vermillion Lakes, with a view of Mt. Rundle (easily accessible, but sometimes crowded):