For example, the Barcode Scanner app takes up: Total: 0.96MB Application: 0.92MB Data: 40KB on the phone. When I move it to the SD Card, it changes to: Total: 524KB Application: 484KB Data: 40KB How come it changes?

I have a G1 phone. I made a partition to install applications on the SD Card using Apps2SD. But I don't like it, I'd like to decouple the specific SD Card from being a requirement to using the phone. How do I undo Apps2SD? I'd like to have Apps only on the phone now.