Uninstalling NIS 2004 -no product key

I have NIS 2004 on my Win XP SP3 IE6 Packard Bell Imedia 1604 computer.  It came already installed and no product key was supplied.  I intend to upgrade to NIS 2009 and NIS support have given me the link to upgrade telling me that a removal tool is inbuilt in the latest NIS 2009 and all I have to do is install over NIS 2004.  I am concerned about this because having Googled and seen all sorts of different ideas about uninstalling and installing  a lot speak of requiring the product key from your old program during  uninstall which I find it hard to believe but I don’t want to be stuck with an incomplete uninstall because I don’t have one.  Probably  the old product key is only required to take advantage of free upgrades to the new one but I can’t find a clear confirmation that this is the case.  It seems ridiculous otherwise.  Surely I only need the product key for my new install.  I wish to clear NIS 2004 altogether and then install the NIS 2009 version.  Furthermore NIS 2004 doesn’t appear in “Add/Remove Programs” but  “Live Reg (Symantec Corporation)” and “Live Update 3.0 (Symantec Corporation)” do. I shall be grateful for some advice.