Peel pears, leaving stems intact. Place them in a large, nonaluminum pot with enough water to cover. Add sugar, spices and lemon juice. Cover pears with a round of wax paper cut to fit interior of pot. Bring to a boil, reduce to simmer and cook until pears can be easily pierced with a knife. Slice away skin and pith from oranges. Remove pears to a serving bowl and add enough syrup to cover. Place oranges in cooking liquid and simmer for 15 minutes or until tender. Peel and seed melon. Cut into long, 1" wide strips. Add melon strips to the poaching oranges and simmer for 5 minutes. Remove to serving bowl. Add grapes and lemon slices to poaching liquid and simmer for 3 minutes. Remove to bowl. Add curry powder to liquid and whisk to dissolve. Cook syrup until reduced by half. Strain through a double thickness of dampened cheesecloth. Drain away any juices that have collected in serving bowl and pour syrup over fruits. Serve fruit with a little of the crystallized ginger sprinkled over each portion.