Idaho Falls has many of the traditional chains out 17th street by the mall or down on the west side of the river.  Also by the river are several great places.  Whitewater grill just opened.  A little pricey but delicious.  Smitty's on Broadway is very popular for breakfast.  Local steak places along the river (Lindsay Blvd) include Jakers and the Sandpiper.  The Cellar, one mile east of Grand Teton Mall, offers fine dining and international cuisine in a 100-year-old renovated house with a full bar and live music.