Make the lemon-parsley yogurt ahead by combining chopped parsley with the yogurt, adding fresh lemon juice and salt & pepper to taste.
Grill vegetables until you get nice grill marks. About 10 minutes depending on your grill.
Season the salmon and shrimp with pepper and salt, I also added some paprika/taco seasoning. Drizzle olive oil before adding to grill to prevent it from sticking.
Let grill until just done, middle of salmon is still pink.
Serve with yogurt dressing.