Any vanilla flavored yogurt can be used. Pick a yogurt that you like the taste of as you will be able to taste it in the ice cream. If you like sweeter yogurt, use that. If you like yogurt that is a bit more tart, use that. You can even use yogurt that has additional peach flavors added to it. You can even use plain yogurt or plain Greek yogurt. If you use plain yogurt, you can add a little vanilla extract to add to the vanilla flavor.