That looked just the job but I have checked right through the list of programs on "Uninstall or change a program" . The only Security programs that I have deliberately installed are AVG (free version) and Spybot S&D. Norton was uninstalled and seems to have gone and there is something called Infineon Security Platform which is not initialised. I have not yet found out what this is or if it is a good thing to have.
On this computer (XP desktop) I run AVG, Spybot S&D, Spywareblaster and Adaware and hope to do likewise on the Vista machine.
I'm not sure about Vista, as I run XP Home, but, last year I had a major problem with a previous version of ZA. I had fixed the problem, and uninstalled ZA, but it wouldn't reinstall. Basically, the truevector services were corrupted, so without asking anyone (I was lucky it worked), I deleted the folder, and tried again, this time it installed.
When I bought it I asked for Norton to be removed and they said that they would. It seems that it is not removed completely because, although I can't see it anywhere, when I last started the laptop after having to kill it with the long press on the power button (It had locked up for ages.) I warned me that Norton is out of date.
I will now download the removal tool and see if that clears any remaining detritus.
I will be back later to tell you what has happened.