In a 2-quart (2 liters) saucepan, bring water and milk to a low boil. Stir in uncooked oats, coconut, pecans, and pineapple. Reduce heat and simmer covered for 10 to 15 minutes, stirring occasionally.
Spoon into bowls and garnish with additional coconut and pineapple. Serve with butter, brown sugar, and milk (nut or coconut milk) if desired.