Bring a large pot of lightly salted water to boil. Add pasta and cook until al dente, about 8 to 10 minutes; drain. Transfer pasta into a large bowl and mix in 1 tablespoon olive oil; cover, and refrigerate until cool.
Place lentils into a small saucepan, cover with water and bring to a boil. Cover and simmer over low heat until lentils are tender, about 15 to 20 minutes. Drain and set aside to cool.
Combine the remaining olive oil, vinegar and garlic in a small bowl.
Remove pasta from refrigerator; add lentils, oil mixture, olives, feta cheese, red onion, mint and dill; stir until thoroughly blended. Season to taste with salt and pepper. Cover and refrigerate for at least 2 hours.