Thanks dhl 6213, looks like it´s always you who are helping me out....
I understand my P2P habits are responsible for my getting in trouble with malware.
I also understand my memory is not ideal for Windows XP. The problem is that this PC comes with the emergency restoration disks so if the hardware is changed, then I can´t restore the original setup anymore. Ever. I guess that leaves me with two option: change the whole PC or settle with this one and get used to it being slow. But what about NOD32 - what is your opinion on this antivirus program?
(P.S. as soon as I find some time I want read all the threads you linked me)