In a large bowl, combine bulgur and water; let stand for 1 hour. Mean while, prepare lemon-oregano dressing. If necessary, drain bulfur well. Add dressing, parsley, pistachios, and tomatoes to bulgur; mix lightly. Serve, or cover and chill up to 3 hours. Mound tabbouleh in a bowl lined with lettuce. Lemon-oregano dressing: Combine 1/4 cup lemon juice, 1/2 tsp. each grated lemon peel and dry oregano leaves, 1/3 cup olive oil or salad oil, 1 clove garlic (minced or pressed), and 1/4 teaspoon freshly ground pepper; mix until well blended.