Scrub potatoes; place in large saucepan with salt. Add boiling water to cover; bring to boil over high heat. Cover pan and reduce heat to low; simmer 30-35 minutes or until potatoes are tender. Drain, peel and cut potatoes crosswise into 1/4" thick slices.
Preheat oven to 375. Using butter, margarine or solid vegetable shortening, thoroughly grease a 2 qt deep casserole dish.
Peel bananas; cut into 1/4" thick slices. In medium bowl, place bananas and orange juice; toss to coat. In small bowl, mix brown sugar with cinnamon. Set aside.
In bottom of prepared casserole dish, arrange 1/3 of the potato slices in a single layer, overlapping the slices slightly. Top with half of the banana slices and sprinkle with 1/3 of the sugar mixture. Dot with 1/3 of the butter.
Repeat layering with another 1/3 of the potato slices and the remaining bananas, reserving some bananas for the top. Sprinkle with 1/3 of the sugar mixture and 1/3 of the butter. Top with remaining potato slices; arrange several banana slices on top. Sprinkle with remaining sugar mixture; dot with remaining butter and pour on rest of orange juice. Bake 45 minutes or until bubbly.