Windows 7: Itunes won't recognize my iphone & won't update either

Seems both problems started simultaneously. My itunes stopped recognizing my Iphone and whenever I try to download any new updates for itunes it downloads it but won't allow me to install it. I don't want to reinstall itunes because I put hundreds of hours into sequencing it the way I want it. By that I mean wording the songs the way I want, rating them all, and also manually putting in the proper album covers. Does anyone know a fix for this problem? I'm running Windows Vista and own the original iphone 4.