Adjust oven racks to center position and lowest position. In a small bowl combine apple juice, pineapple juice, Calvados, brown sugar, allspice, peppercorns, and bay leaves. Place ham on its side in center of pan. Pour 1 cup of the juice mixture over ham; pour remaining juice mixture into bottom of broiler pan. Bake ham in a 325 degree F oven on center oven rack for 1-1/4 hours or until an instant-read thermometer inserted in center of ham registers 135 degree F. Increase oven temperature to broil. Baste ham with pan drippings. Broil ham 4 inches from heat for 4 to 5 minutes or until top is golden brown.
Meanwhile, for pear sauce, arrange Bosc pears on a baking sheet. After ham bakes 15 minutes, bake pears on lowest oven rack for 30 minutes. Turn and bake about 30 minutes more or until golden brown. In a medium saucepan combine Bartlett pears, granulated sugar, cider vinegar, fresh ginger, and vanilla bean. Bring to boiling; reduce heat. Simmer, uncovered, for 10 to 15 minutes or until Bartlett pears soften but still retain their shape. Remove from heat; cover and let stand for 20 minutes. With a slotted spoon or tongs, remove vanilla bean and ginger; scrape vanilla seeds into pear mixture. (Discard pod and piece of ginger.) Stir baked pears into saucepan.
Transfer ham to a cutting board; let stand for 15 minutes. Meanwhile, pour pan juices into a glass measure; remove bay leaves. Let stand for 5 minutes. Skim fat from pan juices. Serve ham with pan juices and pear sauce. Makes 12 servings.