Drain pears, reserving juice. Add enough water to juice to make 1 1/2 cups liquid. Dice pears. Dissolve strawberry gelatin and 1/4 teaspoon salt in 1 cup boiling water. Add 3/4 cup pear liquid and lemon juice. Chill until slightly thickened; stir in pears. Pour into a 6-cup mold or 2-quart rectangular dish; chill until set but not firm. Dissolve lime gelatin and 1/4 teaspoon salt in 1 cup boiling water. Add remaining 3/4 cup pear liquid. Chill until slightly thickened. Combine cream cheese and ginger; gradually add gelatin, beating until smooth. Stir in nuts. Spoon over strawberry layer and chill until firm. Serves 10 to 12.