Montana

Did it the other way round in 2001,flew to Calgary transfer to Fernie took about 5 hours due to the driver going in the wrong direction for 1 hour after leaving the airport.Stayed 1 week in Fernie then went to big Mountain for second week.I think it took around 3 hours transfer from one to the other including time spent at border control.

Bozeman to Vancouver must be 20 hours by car. Fly to Denver or Chicago and get a plane to Bozeman. Between Bozeman, Sun Valley and Jackson you will find what you need. If you are going to go to Sun Valley, Jackson, Big Mountain, etc, drive one way, and fly out back thru Chicago or Denver.

If you are skiing out of Bozeman you have Bridger within 20 minutes, Big Sky/Moonlight Basin around a hour and Discovery about 2 hours west (Philipsburg). Red Lodge is at least 3 hours.
Probably the most bang for your buck is the Biggest Skiing in America Pass (www.BiggestSkiinginAmerica.com) that combines Big Sky and Moonlight Basin- about 5500 acres and 80k xskiing. Pretty hard to beat that.

I know this is outdated but in case anyone from the UK was considering skiing in Montana. We had a ranching holiday there in July and stayed hour south of Great falls and 30 west of Helena both towns had airports and I know there were ski resorts within an hour of the ranch. Most direct flight we found was Heathrow to Minneapolis then internal to Helena/Great Falls/Billings/Bozeman. We loved Montana.

From personal experience you cannot go wrong with Big Mountain / Whitefish which is nearby. As for Canada I like central BC better than Whistler dry soft snow and not so large and crazy. Big White is my first choice then Sun Peaks as my second choice. That far north the weather is much better in Feb and March. I have spent a week at Big Sky in late Jan when the high temp was negative 10F for the whole week. Have FUN