Preheat oven to 400°.
Cook pasta according to the package directions, omitting salt and fat. Drain well.
Combine hot water, roasted red bell peppers, and cream cheese in a food processor; process until smooth, scraping sides.
Heat the oil in a Dutch oven over medium-high heat. Add salt, shrimp, scallops, and garlic; sauté 2 minutes or until shrimp and scallops are almost done. Add pepper mixture to pan; bring to a simmer. Reduce heat; cook 2 minutes, stirring frequently. Add pasta and parsley to shrimp mixture, tossing well to combine. Spoon pasta mixture into an 8-inch square baking dish lightly coated with cooking spray, and sprinkle evenly with cheese. Bake at 400° for 20 minutes or until cheese melts; remove from oven.
Return dish to oven; broil 2 minutes or until cheese begins to brown. Remove from heat; let stand 10 minutes.
Let the dish stand a few minutes after it emerges from the oven so the sauce can set.