This is a tried-and-true favorite.  My aunt Midge used to bring it to all family functions, and it was always the first to disappear! 
Strawberry Nut Jello Salad

Combine Jello and water, stir until dissolved, and add the strawberries (with the juice), nuts, pineapple, and bananas.  Pour half into the jello mold (or a bowl, if you don't have  a jello mold) and refrigerate one hour.  Spread the sour cream on top of it, add the rest of the jello mixture, and chill another hour.