Help with resetting my phone

[GruffyMcGuiness]

I rooted my phone a few months ago and never really did anything needing my phone to be rooted. Then, I replaced my music app with another music app which I assume isn't allowing me to update to ICS... It fails every time. My phone still shows Superuser but I used a root checker app and it says my phone isn't rooted. How can I get the files back to how they were and get rid of Superuser?

 

[tcrews]

RSDLite and Fastboot the ICS fastboot files. Then you don't even have to worry about getting the OTA as you will already be at ICS.