Combine flour, salt and baking soda. Preheat oven to 350 degrees F. Beat shortening, sugars and vanilla in a large bowl until creamy. Beat in eggs until light and fluffy. Gradually beat in the flour mixture and rolled oats. Stir in raisins, if using. Drop by well-rounded teaspoonfuls onto greased baking sheets. Bake for 8 to 10 minutes or until golden. Cool cookies on sheets on wire racks for 2 minutes then transfer cookies to wire racks to cool. Makes 5 dozen; 7 1/2 dozen with raisins.