Preheat oven to 450 deg. F. Heat oil in heavy medium skillet over medium heat. Add zucchini, yellow squash and crushed red pepper; saute until vegetables are almost tender, about 5 minutes.
Place pizza crust on baking sheet. Spread mushroom sauce over. Sprinkle with garlic, then mozzarella. Top with squash mixture and tomatoes. Sprinkle with Parmesan cheese. Bake pizza until cheese melts and crust is crisp, about 13 minutes. Cut into pieces.