pacostaco

I have slight experience with rooting a phone, but none with unrooting a phone. I bought a Samsung Galaxy SGH-I897 from my Hall mate on campus, and have no idea what rom it is running not only that but it will not allow me to access the sd card through my computer after downloading several drivers. Even enabling the ability to use it as mass storage will not work, the option to mount and unmount do not even show. So i was wondering if anyone on this form could even give slight incite on what to do and how to do it.