Bring a large pot of lightly salted water to a boil. Cook pasta in boiling water for 8 to 10 minutes, or until al dente; drain. Bring 1/2 cup water to a boil in a saucepan, and cook the spinach 4 to 6 minutes, until tender.
Place the cooked pasta in a medium bowl. In a small bowl, whisk together the eggs and oil. Toss the pasta with the cooked spinach, egg mixture, and bread crumbs.
Cover the bottom of a 9x13 inch baking dish with 1/3 of the pasta sauce. Pour half of the pasta mixture into the baking dish, and cover with another 1/3 of the pasta sauce. Sprinkle with half of the Cheddar cheese and half of the mozzarella. Layer with remaining pasta mixture, and top with remaining sauce. Sprinkle with the rest of the Cheddar and mozzarella cheeses.
Bake 45 minutes in the preheated oven, or until bubbly and lightly browned.