Maxbert, building on what srobarts wrote, I would suggest that you download the Windows SP3 file and copy it to CD to install it from there rather than rely on MS Update. I have found it a more reliable (and much faster) approach in this circumstance.
It is also much better to install SP3 before loading any AV or firewall software - and therefore safer to do it off-line, i.e. from CD.
While you may have no problems installing all the drivers from the Windows XP installation disk, I would think it prudent to seek out and note down the details of (and all the drivers for) the main components - graphics, sound, network at least. Always better to know what you are searching for when you can't find a driver!
SD