Arrange summer squash, onions, and bell pepper on a baking sheet. Drizzle with olive oil and vinegar. Sprinkle with garlic, oregano, black pepper and sea salt. Toss together on pan to distribute ingredients.
Place on top rack of oven and roast for about 30 minutes, until golden brown and tender. When done, remove from oven and set aside.
To toast pine nuts, place them in a small baking dish in the hot oven for about 5 minutes while vegetables are roasting. Remove and set aside.
Meanwhile, bring water to boil in a medium pot. Add pasta and cook to al dente stage (according to package directions). Place in colander and rinse and drain.
Add marinara sauce to pot and heat until bubbling. Remove from heat and add cooked pasta, stirring gently to distribute ingredients.
Divide pasta with marinara sauce among 4 pasta bowls (or plates). Top with roasted vegetables, pinenuts, fresh basil, and Parmesan cheese (if desired).