Well, why not let it install, and then remove it using Add/Remove programs... if possible. Otherwise, you can use Revo Uninstaller... or Windows Installer Cleanup Utility to remove it fully from your PC.
It might also be worth looking at... how is it asking for installation again and again? You can have a look at the startup programs... and see if anything related to Roxio is there. You can make use of the small yet wonderful
WhatInStartup program for that... which lists the programs that startup when windows boots.