I am trying to uninstall itunes from old e-mail account and reinstall. I am not able to uninstall. Will not allow.

Hello, I recently hooked up my PC from which I haven't used for a couple years. I have downloaded the new version of Windows 8. I am trying to uninstall my old itunes. I lost my password and have since changed my e-mail address. I am not able to access the current itunes that is installed. So would like to remove that old version. I have removed the icon however it will not let me remove itunes program. I want to start a new account with my new e-mail address.

My old account had a Nano and I have just purchased IPod 16GB

Amy