Bring potatoes and water to cover to a boil in a large Dutch oven over medium-high heat, and cook 20 minutes or until tender. Drain.
Meanwhile, cook green beans in boiling water to cover in a medium saucepan 3 to 4 minutes or until crisp-tender. Plunge in ice water to stop the cooking process; drain.
Whisk together vinegar and next 5 ingredients in a medium bowl. Add oil in a slow, steady stream, whisking constantly, until smooth.
Pour vinegar mixture over potatoes. Just before serving, add green beans, dill, and parsley, and toss gently until blended. Sprinkle with bacon. Serve immediately, or cover and chill until ready to serve.