Melt the butter in a large saucepan over medium heat, and add spaghetti.
Sauté spaghetti for 5 minutes or until lightly browned. Add the rice, stirring to coat. Stir in the water, salt, and pepper, and bring to a boil. Cover; reduce heat, and simmer for 20 minutes or until the liquid is absorbed. Remove pilaf from heat, and let stand for 10 minutes. Fluff with a fork.