Start by making the simple syrup: place the sugar and water in a glass measuring cup and microwave for 45 seconds. Remove from microwave and stir with spoon until sugar dissolves. Let chill completely.
When you're ready to make the sangria slushees, place the wine, peaches, raspberries, orange juice, brandy and chilled simple syrup in a high speed blender. Puree until smooth. Pour in four glasses and garnish with raspberries and lime slices if you wish.