I have been told that if you allow microsoft to scan your computer then microsoft will only download what you need.So why do they download a firewall and anti virus when I have them already?!! I did install it and my computer went to a crawl and spent ages connecting to the internet.It is sooo confusing.When I disconnected xp2 anti virus/firewall, it said that although it has been disabled it will still show that it is on! I have given up and have un-installed it. If there are any serious glitches in xp why do'nt they have single patches to install? It would be much easier and if one caused the computer to slow or whatever then you know the culprit and can adjust or delete it!!!
SP2 will download and install only the required files, there is no anti-virus included in the update or the original program. If you have a third party firewall installed then SP2 will recognise this and offer you the choice of which to use, the firewall update is downloaded because a firewall is already part of XP.