In a medium-size mixing bowl, combine cream cheese, ranch dressing mix, and green onions. Spread this mixture on each tortilla. Sprinkle red pepper, celery, black olives, and cheese (if you'd like) over the cream cheese mixture. Roll up the tortillas, then wrap them tightly in aluminum foil. Chill 2 hours or overnight. Cut off ends of the rolls, and slice the chilled rolls into 1 inch slices.