If you are not keeping the PC you may want to consider wiping the disks. But why would you specifically need to uninstall software ? Just concentrate on installing it on the new one.
Sorry to be a pain and thick but I pay for my security along with my monthy subscription of broadband. Been like this for nearly 5 years. Now I will be only using 1 computer so this is why I want to know if I have to uninstall it from this pc as I have the disc then reinstall it on the new one. Hope I have simplflyed it .