What do you think happened?

Something fairly serious occurred to my computer recently. While working with folders (checking, analyzing data, transferring material, etc) for about 20 minutes, Windows Explorer would start to be unresponsive, the window would play up, the order of the folders would become random, and given more time the whole computer would freeze. (see screen shots).

As I'm well protected, at first I thought my hard drive was dying, and the only thing that I could do quickly enough was to click restart. Once rebooted the whole thing would remain normal for a while (about 20 minutes) and then start again the same degenerative process.

I had my machine checked by Asus service, and they told me my Hard drive works perfectly. So I thought it must be malware: Avira, MBAM, Hitman Pro found nothing, I know I should have tried other scanners but I thought I'll restore an image old enough to be on the safe side. It worked, the problem disappeared, but I'm curious, what was it?

Anybody who has encountered something similar? Forgive me for the quality of the screen shots, but I had to use a cheap digital camera as the computer wouldn't allow me to take screen shots. Two of the photos are about the problem, and one shows the window as it is normally.

 

Sounds like your Icon cache became corrupt. Not really sure what the cause was. I don't think that it's malware related though. Check out this link for a solution if it happens again. http://forum.thewindowsclub.com/windows-tips-tutorials-articles/20099-how-rectify-corrupt-icons-problem-windows-vista.html

 

Might be bad sectors?
Run CHKDSK to see if it does anything.

 

It is good to know about the icon cache, thanks. My question is if the icon cache was corrupted if would happen all the time, instead Windows Explorer would function perfectly for the first 20 minutes after every reboot. From memory it was triggered the first time by a file that had been copied from a collaborator's flash drive (at the time I was protected by Rollback Rx, and it didn't worry me so much).

@ Noob
Yes, I remember running check disk when it first happened to no avail.

 

It's a crap shoot really. Maybe trying MTest and testing your RAM out. A bad stick can make things unstable. Just throwing out suggestions.

 

I experienced similar situations occasionally over the years on systems that have minimal RAM (less than 2GB for any Windows version is what I would consider minimal now) when misbehaving applications gobbled too much RAM or handles and didn't release it/them. (Adobe, you know I'm talkin' 'bout you...)

The system would "stutter" and be slow for a few minutes and the graphics display would start to be corrupted, then the system would freeze. Rebooting always cured it, of course.

In WinXP's Task Manager the Performance tab shows the RAM and handles in use; I believe there are Microsoft Sysinternals tools that can show more detailed information.