Bring 2 quarts of water and the salt to a rolling boil in a heavy saucepan. Stir in the orzo and cook it for the length of time specified on the package, until tender. Pour the cooked pasta into a colander and drain thoroughly so that no excess water remains.
Place the well-drained orzo in a large serving bowl. Add the chopped Kalamata olives, red onion, diced sun-dried tomatoes, sliced spinach, lemon zest, basil, and mint. Stir well until the vegetables, herbs, and pasta are evenly combined.
Add the black pepper, extra-virgin olive oil, fresh lemon juice, and crumbled feta to the orzo mixture. Toss gently until everything is evenly coated and incorporated, taking care not to break the feta into excessively small pieces.
Serve the salad at room temperature, or refrigerate it until serving. For a more developed blend of flavors, allow the finished salad to rest in the refrigerator for at least 30 minutes before serving.