Tips: Keeping the skin on when grilling salmon helps hold the fish together and protects the delicate flesh from the searing heat. Once cooked, the skin slips off easily.To oil a grill: Oil a folded paper towel, hold it with tongs and rub it over the rack. (Do not use cooking spray on a hot grill.) When grilling delicate foods like tofu and fish, it is helpful to spray the food with cooking spray.
Stir together yogurt, parsley, cilantro, lemon juice, oil, garlic, paprika, cumin, salt and pepper in a small bowl. Reserve 1/4 cup for sauce; cover and refrigerate. Place salmon fillets in a large sealable plastic bag. Pour in the remaining herb mixture, seal the bag and turn to coat. Refrigerate for 20 to 30 minutes, turning the bag over once.
Meanwhile, preheat grill to medium-high.
Oil the grill rack (see Tip). Remove the salmon from the marinade, blotting any excess. Grill the salmon until browned and opaque in the center, 4 to 6 minutes per side. To serve, top each piece with a dollop of the reserved sauce and garnish with lemon wedges.