Window Explorer Crashing-Because Of Videos?

This all started about 3 days ago. (6/14/2007) First, I have a lot of videos on my comp, so I have separated them into different folders for whatever different kinds they are, so I have a few individual folders containing different kinds of vids.
Now, starting those 3 days ago, there were 5 of those folders that, when I'd try to explore them for a video, I'd get this message popup: "Windows Explorer Has Encountered A Problem And Needs To Close," and would then close. Sometimes, Explorer would start on its own, and sometimes, I'd have to restart it through Task Manager. Also, along with this, but only about once every 5 times or so, I'd also get this popup: "Dr. Watson Postmortem Debugger Has Encountered A Problem, And Needs To Close."
First thing I thought, it was some sort of malware, but after doing numerous scans (SpySweeper, SpyBot, NOD32, and Ad-Aware) came up with nothing that seemed to cause the problem. Then, I went through every folder, and rooted out 19 different video files scattered throughout those folders that were the ones causing the Explorer crashes. It turned out that it wasn't just one certain kind of video, or any I got from one certain source, but it was all different kinds that I had found from various places. I did also think it was odd that these vids would be doing such a thing, since they hadn't done it even the day before, and the fact that nothing else does this, just those vids, wherever they're placed. (Except the desktop-but I don't like that to be cluttered.) Also, nothing else is affected, and will still run normally.
Any searches on the internet I've done have come up with nothing. Microsoft's website has nothing on the problem, either, and I'm getting pretty frustrated that I there seems to be no reason that I can find that would be causing this problem. To everyone who helps me here, I greatly appreciate it.

 

Oh, I should've mentioned that I am using Windows XP SP2 as my OS, on a Dell Dimension 1100. Everything on the comp is factory, except for the DVD ROM/CD Burner, and the second hard drive I installed (Western Digital).