Cook potatoes in boiling water to cover and salted with 1 teaspoon salt 40 minutes or until tender; drain and cool 10 to 15 minutes.
Stir together mayonnaise, mustard, pepper, and remaining 1 1/2 teaspoons salt in a large bowl.
Peel potatoes, and cut into 1-inch cubes. Add warm potato cubes and grated eggs to bowl, and gently toss with mayonnaise mixture. Serve immediately, or, if desired, cover and chill.