Help! i can't seem to download Itunes or quicktime

I had to upgrade my ipod touch. However i can't seem to upgrade my itunes. I deleted my quicktime, and now my itunes doesnt open at all. I try re-installng Quicktime but it is not installing. I keep getting a error message that says; The installer has insufficient privileges to modify this file : C:/Program files/Java jre6/lib/ext/QTJava.zip. Please help... I want to atleast get my old itunes working so i can rstore my applications that i backed up on it. Howeveri cant even open itunes now because i have nomore quicktime on my computer