Cook spaghetti according to directions on package; drain and rinse in cold water.
In a large bowl, combine zucchini, tomatoes, cucumber, bell peppers, onion and black olives.
In a small bowl, whisk together Italian dressing, sesame seeds, parmesan cheese, paprika, celery seed and garlic powder.
Add cooked spaghetti to vegetables and olives; add dressing and toss together thoroughly.
Cover and set in refrigerator to chill for at least 3 hours; serve chilled.