Preheat grill to medium-high.
Place all cut vegetables and the tomatoes in a large shallow baking dish, add the 1/2 cup of olive oil, and toss to coat. Season with salt and pepper, to taste. Place the vegetables on the grill and cook for 5 to 6 minutes, turning halfway through the cooking time. Remove the tomatoes, cover grill, and cook the remaining vegetables for 2 minutes, or until almost cooked through. Transfer vegetables to a cutting board and coarsely chop (leave tomatoes whole). Place the chopped vegetables and tomatoes in a large bowl, add the 2 tablespoons of olive oil, garlic, oregano and parsley and season with salt and pepper, to taste. Serve at room temperature.