To make the salad, boil the potatoes until firm/tender. Cool to room temperature. Place in a bowl with the other salad ingredients. Toss to combine. Keep salad in the fridge until the fish is cooked.
Brush the salmon lightly with olive oil; sprinkle with oregano, chili powder, salt and pepper. Preheat grill to medium-high. Cook, lightly oiling the grill if not non-stick, 3-4 minutes per side, or until cooked through. (Salmon could also be baked in a 400 degrees F oven for 12-15 minutes). Divide and arrange salad on plates. Top with salmon and serve.
Note: To blanch vegetables, cook into boiling water until firm/tender. Cool in cold water, and then drain well.