Bring 3 cups water to a boil, and add shrimp; cook 3 to 5 minutes or just until shrimp turn pink.
Drain and rinse with cold water.
Peel shrimp, and devein, if desired.
Toss together pasta, vinegar, salt, and pepper. Line a large platter with lettuce leaves; spoon pasta in center, and top with shrimp. Arrange tomato and bell pepper around pasta.