Cook pasta according to package directions, omitting salt and fat; set aside.
Coat a small nonstick skillet with cooking spray and place over medium-high heat until hot.
Add onion and garlic: saute 3 minutes.
Remove from heat;set aside Combine 1/2 cup mozzarella cheese,1/4 cup Parmesan cheese, Italian seasoning, pepper, ricotta cheese,and softened cream cheeses in a bowl; beat at medium speed of a mixer until smooth.
Stir in onion mixture and spinach.
Spoon cheese mixture into cooked manicotti.
(about 1/3 cup per shell) Divide 1 cup pasta sauce evenly between 6 individual casserole dishes coated with cooking spray (if you don't have individual casserole dishes,use a 13 x 9 inch baking dish).
Arrange 2 stuffed manicotti in each dish.
Pour remaining sauce over each serving.
Place dishes on a baking sheet.
Cover each dish with foil and bake at 350 for 25 minutes.
Sprinkle with remaining mozzarella and Parmesan cheeses; bake uncovered an additional 5 minutes.
Garnish with oregano, if desired.
Yield 6 servings (serving size 2 manicotti for 8 pts).