Preheat oven to 400°F Grease 13" by 9" glass baking dish.
Prepare filling: In large bowl, toss peaches with lemon juice. Add Whisky, granulated sugar, and 1/4 cup brown sugar; toss to coat. Spread mixture in baking dish and dot with 2 tablespoons butter.
Prepare topping: In large bowl, mix flour, cinnamon, and 1/2 cup brown sugar. With pastry blender, cut in 10 tablespoons butter until coarse crumbs form. Press crumbs together into 1/2-inch clumps; sprinkle over peaches.
Bake crisp 30-35 minutes or until topping is brown and fruit is hot and bubbly. Cool 20 minutes. Serve warm with frozen yogurt if you like.