Rooting and unrooting is simple. Use Matts utility and you can do either. The only thing rooting does it give you super user permissions. If you don't mess with anything after rooting, then nothing changes. But you can brick your phone if you mess with the wrong things. Make sure to read, read and read some more. Once you have it memorized, read it again lol. Just to be safe. I use root only to freeze bloatware and perform backups. I also use to use it for screen shots, but that is a standard feature on ICS. Oh I also use root to block ads on free apps. I don't flash roms or mess with anything I don't know about(which is almost everything)
When you root, Superuser is added. No settings are changed.
When you unroot, Superuser is removed. No settings are changed.
Make sure you reset anything you have done while rooted i.e. froze bloatware. I don't know what happens if you unroot with things still frozen but I would imagine they'd stay that way forcing you to reboot, defrost everything, unroot.
