In a blender or food processor, thoroughly mix cream cheese, sour cream and mayonnaise. Spread the mixture evenly in the bottom of a medium serving dish.
In individual layers, top the mixture with cocktail sauce, mild salsa, diced green onion, red bell pepper, green bell pepper, shredded Cheddar cheese and shredded lettuce.
Arrange cucumber slices around the edge of the serving dish. Chill in the refrigerator at least 2 hours before serving.
