I have Kapersky on a 2004 2.0GHz HP Pavillion and an 2009 Acer Dual Core 2.1GHz both running XP Pro from a clean original install (i.e. not the manufacturers disc). I also set regular restore points before I install anything and 'auto' update is OFF. I haven't had any problems this year on either PC so far although I've noticed an awful lot of patches for Windows, Explorer and Flash.
I have to take up this point though......
I'm not so sure. Been installing computers since 1995 (Mac and PC) and you have to understand that there is a whole industry making a good living out of this including Microsoft (certified technician programme/commercial updates/support), Norton, Kapersky and others. I cannot help thinking that these people are either complicit or they are at least not taking a pro-active stance to 'mend' Windows effectively.
Windows 7 still has some DOS routines at its core and the system is inherently weak in terms of security due, amongst other things, to a reliance on the registry and Internet Explorer which I think has been patched 20 or so times this year. Unix, on the other hand, was built as a multi user platform from the outset and any attempted change to a system level setting is prohibited - it has never been hacked without a root level admin password. Safari (web browser on Mac) effectively works within a sandbox - it can be crashed deliberately but it cannot be used to hack the OS.
If you look at what happened on Mac when they went to Unix around 2000 - Norton was one of the most popular Apple purchases for protection, maintenance and optimisation i.e. everyone bought Norton who ran a Mac. Unix does all this itself and...... Norton is now dead on the Mac and withdrawn from the platform (as is all the other virus/protection software) because frankly it is redundant. The problems on Windows are keeping Norton and others in business.
Whilst there may be the odd fruit-case sociopath who believes in fame by destruction, I think that this is a myth supported by the mainstream. I know (of) some of these people and the vast majority are NOT black but rather white... i.e. they do not make malicious hacks. Gary McKinnon comes to mind - he just wanted to get into Nellis to see the UFO's and that is probably why they want him banged up - because he began to tell people what he had found including folders with before and after retouched NASA photos.
One of these people I know is ex military - his job was to sneak into enemy installations, put in a permanent hack and get out without them knowing anything - the enemy continue as if nothing has happened and we (West) can see everything they are doing. He is now retired and a commercial IT security bod but he still supports the community with his knowledge. Black hacking is frowned upon and will get you burned by the community, or at least marooned. It draws too much attention for one thing. McKinnon was COVERT for over 2 years across various military and university (used as cover for many NASA projects) networks and pretended to be a US Gov IT technician with a remote connection whenever someone logged on and asked him why he was connected to their PC. But he never left any damage and that is the point.
The main source of malicious attacks is much more likely to be from Latvia, Russia mob, India and possibly North Africa - they would be after your personal/bank details so that they can rob you. The banks are getting hammered and covering it up to save face but that is another story for another night.
It's been suggested that Russia/China or a similarly diametric region might try to kill Windows on mass with a virus to disrupt and basically knack up everyone, the economy and infrastructure but this is unlikely for many reasons, not least the fact that they trade and invest in the West and that would kill them as well. Ditto the powerful oil states. Libya, Irac and Kim Jong IL haven't really got the where with all.
You have to ask yourself the questions a professional investigator would - who has the motive, the opportunity and stands to gain the most. For me the most likely answer is Microsoft themselves and all of the companies that feed off repairing and maintaining Windows for their living.
Think about it..... MSoft are worth $42 billion dollars and they cannot fix Windows. Even after 20 years. It just does not add up. Or maybe it does....