Preheat oven to 375°. Combine lemon juice, chopped fresh oregano, olive oil, and garlic in a large zip-top plastic bag. Add chicken, and seal. Marinate in refrigerator for 30 minutes, turning bag occasionally. Place chicken on a jelly-roll pan coated with cooking spray; sprinkle with salt and pepper. Bake at 375° for 30 minutes or until done, turning after 15 minutes. Sprinkle with chopped fresh parsley and chopped olives.