Ok I rooted my gf's phone so she could tether, and now I want to unroot her for 2.2. I've downloaded DI01package3.tar.md5, but I have no idea what to do with it. I saw ODIN thrown around, but have no idea what that means or how to do it. I have the AndroidSDK and all that jazz installed, so maybe its an acronym that I don't know what it means.
Also, will she loose all of her information? Is it basically wiping all her data and flashing a new os?