Jojo5000 has made some good suggestions. Best value meals in town in my opinion are at Bumpers and Melisa's. The Thai place is decent but most of the others are just chain restaurant food with much higher prices. There used to be lots of decent places but the quality has gone down in recent years. There are still great places to eat and drink it is just that they are harder to find and off the beaten track. The Japanese place on the corner near the Paddock and the Greek place is good for a cheap eat. For great Pizza I think that Athena pizza is the best (upstairs in the clock tower mall). If you want to really treat yourself,
go to the Banff Centre and try their fine dining restaurant, which although expensive, is one of the best meals I have ever eaten in Banff. They also do a buffet (all courses) at around 24 CAD per head which is excellent value. Aparently they have an agreement with the town not to market the restaurant for some reason to do with it's status as a government funded arts centre, which is lunacy given that there is one of the best restaurants and views in the Rockies up there.
Specials on beer are decent at Melisa's.
Lunch with a soft drink on mountain will set you back between 10 and 15 dollars. Look at paying between 5 and 8 dollars for a beer.
To get you in the mood for your trip - Take a look at this graph of the snow pillow at sunshine village to see what an amazing season it is shaping up to be...
http://www.environment.alberta.ca/apps/basins/DisplayData.aspx?Type=Figure&BasinID=14&DataType=4&StationID=SUNS
Have fun.