Bring a large pot of salted water to a boil. Add the orzo and cook uncovered, over high heat until al dente, cooked through but still a bit firm, stirring occasionally (or cook the orzo according to the package directions). Drain the orzo in a colander and and rinse with cold water. Set aside.
In a large bowl, toss the drained orzo with the rest of the ingredients, the olive oil, chopped parsley, tomatoes, feta cheese, cucumber, oregano, black pepper and lemon juice (add the lemon juice just before serving). Because the feta cheese is salty, taste and add salt if needed. Serve at room temperature.