Good post. I also use AVG, ZoneAlarm, and also run Adaware and Spybot every now and then too. And Firefox helps keep those nasty bugs at bay too. One other simple way (sorry, I did not read the link...) to boost your XP performance, or any operating system, is to install more RAM. Most pc's can take more RAM, and it all helps. My PC is old, and used to have 256Mb, and upping it by 512 mad a big difference, and the extra RAM only cost 20 quid (about 40 dollars I guess).
Other PC tips that I have learnt (that hard way) is to back up important files (photos, videos etc) as hard drives can die (mine did...
). I now have an external hard drive to back everything up to, and put the most previous photos on DVD. Running the disk checks and defrags helps too (but back up before running a disk check - not sure if this is required, but it worries me...)