Bring 4 quarts water to a full boil. Add 1/4 tsp salt and stir in pasta. Cook 5 to 8 minutes or until noodles are tender but firm. While pasta cooks, warm oil in a large sauté pan over medium heat. Add garlic, swirl for a moment and reduce heat to low. Do not let garlic brown. Add zucchini and yellow squash and sauté gently until zucchini softens slightly, about 5 minutes. Season mixture with 1/4 tsp salt and remove pan from heat. When pasta is finished cooking, drain noodles. Using tongs or 2 kitchen spoons, combine noodles thoroughly with zucchini mixture over low heat. Add basil, arugula, and tomatoes and season with remaining 1/4 tsp salt. Sprinkle with lemon zest and juice and stir to combine. Serve immediately.
