1. Preheat oven to 350 degrees. Lightly grease 18 muffin cups or use paper liners.
2. In a large bowl, sift together 2 1/2 cups all-purpose flour, 1 1/2 cups sugar, cinnamon, nutmeg, ginger, baking soda, baking powder, and salt. In a separate bowl, mix together eggs, pumpkin and oil. Add pumpkin mixture to flour mixture; stirring just to moisten. Fold in apples. Spoon batter into prepared muffin cups.
3. In a small bowl, mix together 2 tablespoons flour, 1/4 cup sugar and 1/2 teaspoon cinnamon. Cut in butter until mixture resembles coarse crumbs. Sprinkle topping evenly over muffin batter.
4. Bake in preheated oven for 35-40 minutes, or until a toothpick inserted into muffin comes out clean.