My wife and I recently completed a week-long trip through the Banff-Lake Louise-Jasper corridor and ate very well indeed, mostly thanks to recommendations found here on Chowhound.
When staying in Lake Louise, we actually drove across the BC border to Field and ate at Truffle Pigs. My spring roll appetizer and salad w/ caramelized chicken were both very good, as was my wife's pasta (obviously fresh), but it was her appetizer that had her talking for days. It was, if her memory serves, fresh chanterelle mushrooms in a philo pastry with three cheeses w/ merlot reduction. We had good service as well. Great recommendation from Chowhound; without it there's simply no way anyone we would have stopped in a town as small as Field expecting a meal like the one we had. VERY highly recommended if you're anywhere near the Lake Louise / Field / Golden area.
Our second night in the Lake Louise area we ate at our hotel: the Moraine Lake Lodge. Not bad, really; overpriced, as all hotel restaurants are, but my smoked tomato soup was excellent and our mains (chicken for me, pheasant for my wife) were good, but almost overpowered by seasoning. A decent choice, especially if you're staying at Moraine Lake and don't feel like another trip up and down that godforsaken road.
After driving to Jasper the next day we took another hint from Chowhound and tried Tekarra. My appetizer was a little plain -- the salad that caught my eye was unavailable because of the whole spinach scare thing -- and my wife's involved far too much brie, but my main -- banana-crusted chicken w/ sweet mango curry sauce -- was superb. My wife's arctic char was quite good as well. For dessert we split a decadently huge hot fudge sundae. Our server was great: friendly, helpful, attentive but not overbearing. Highly recommended.
We ate a quick lunch at La Fiesta in Jasper. I thought it was ok, but my wife didn't like it. I guess it depends on what kind of mood you're in; if you've just spent the day hiking up a canyon I guess tapas afterward isn't really going to cut it. Still, I think La Fiesta would be a decent option for dinner under normal circumstances.
Still in Jasper: the Bear Paw bakery. Absolutely great for breakfast, takeaway lunches, coffee, etc. There's often a lineup, but it's worth it; the pastries were among some of the best I've had anywhere.
We drove back down to Banff and stayed there two nights, but didn't have any remarkable meals. We didn't have the energy to try Fuze or Typhoon, so we stuck to the many restaurants in Banff Springs. Can't say I'd recommend anything there but the view. We also went to a place in Banff called Melissa's for breakfast, which I thought was crap. Crowded, slow and the food was unpleasant at best. They also claim to use real maple syrup, but I know pure maple syrup and that wasn't it. If you like your breakfast to be anything other than bland, I'd avoid Melissa's.
On the way from Banff to Calgary we stopped in Canmore for lunch at Crazyweed, another strong Chowhound recommendation. It definitely lived up to the hype; our sandwiches were fantastic, the staff was great and there was a distinct feel to the place. I highly recommend Crazyweed, just as everyone else on this board has.
Finally, in Calgary, we wanted to find a quiet place with interesting beer and decent food. We tried Hop In Brew on 12th Ave, and it was pretty good. Lots of microbrews on tap and, while their food selection is limited to pizzas and a few other simple dishes, the pizzas are excellent. If you like interesting beer and want ok food to go with it, Hop In Brew's a pretty good option.