Cook rice according to package directions, omitting butter. Set aside.
Bring 6 cups water to a boil in a Dutch oven; add shrimp, and cook 3 to 5 minutes or just until shrimp turn pink. Drain and rinse with cold water. Peel shrimp, leaving a few tails intact for garnish; devein, if desired.
Combine rice, shrimp, crabmeat, and next 2 ingredients in a large bowl; add Fresh Herb Vinaigrette. Toss gently. Cover and chill at least 2 hours. Drizzle with lemon juice. Serve over Bibb lettuce leaves with asparagus and tomato. Garnish, if desired.