Preheat oven to 350 degrees F (175 degrees C). Lightly grease a baking sheet.
Preparing Squash
Place spaghetti squash cut sides down on the prepared baking sheet, and bake 30 minutes in the preheated oven, or until a sharp knife can be inserted with only a little resistance.
Remove squash from oven, and set aside to cool enough to be easily handled.
Once the spaghetti squash is cooled, use a large spoon to scoop the stringy pulp from the squash and set aside 3 cups. Save the rest for later.
When squash is cooled
Heat oil in a skillet over medium heat. Saute garlic in oil until browned, 2 to 3 minutes.
Stir in the tomatoes and zucchini and cook only until warm.
Sprinkle with salt and pepper
Bake
Place spaghetti squash in a 8x8 pan, spoon veggies over it, crumble feta on top and bake at 325 for 10 minutes