Fill a medium saucepan with water and bring it to a boil. Cook the zucchini for 10 minutes, until they are soft when pierced with a fork. Rinse the zucchini in cold water, then drain it, and set it aside in a large bowl.
Bring a medium saucepan of water to a boil. Add the potatoes and cook them for 15 to 20 minutes, until they are soft when pierced with a fork. Rinse them in cold water, and then drain the potatoes and add them to the zucchini.
Add the tomatoes, cucumbers, onion, olives, olive oil, lemon juice, eggs, feta, and oregano. Toss the ingredients lightly to combine them.
Add salt and pepper, to taste, and stir the salad gently to mix in the seasoning.
Chill the salad for at least 30 minutes before serving it.
