Certain folders crashing Windows Explorer

Hi.

I'm not sure if this is the right place to post this since it's not entirely BSOD related, so I haven't followed the usual pre-thread-creation requirements.

A few days ago I had a sudden BSOD and trouble booting my computer back up again. I ran some sort of bootup repair and it worked, but my computer has been running abnormally slow since. I managed to fix my internet browsing speed which seemed to be due to a virus, but whenever I try and access certain folders in windows explorer now, explorer will simply crash.

I have tried running in safe mode and disabling thumbnails and the like and none of it seems to work. I looked through this thread:
Clicking on specific folders causes explorer to crash
and none of the context menu handlers would fix the problem, and "DivX" was nowhere to be found.

A wide variety of folders seem to be affected. Some have videos, mostly .avi's, and some have nothing but pictures, mostly .jpegs. I'm pretty stumped as the many solutions online seem to be of no help.

Thanks!

Thanks for the reply. I'm not entirely sure how to uninstall all of my video codecs or what those even are... heh...

Here it is. Thanks!

I installed those codecs and ran a disk cleanup, and my computer restarted itself. Upon booting up again, it ran incredibly slowly, and eventually gave me a BSOD. Upon attempting to boot up again, after the initial screen that said "SAMSUNG" and "press F2 for setup", there was nothing but a black screen with a flashing white cursor on the top left. After waiting a long time, it would read "OS not found."

None of the F# buttons during the "SAMSUNG" screen do anything besides the black screen except for F2 which takes me to the system setup or something along those lines. I checked the boot order and it boots my CD drive first, then my HDD which seems to register. I tried switching the order but that solved nothing.

On another note, after that BSOD, my laptop began making a rhythmic clicking noise, and when I shake it, it sounds like something small is loose inside. I'm trying to find a screwdrive to take a look inside. Apparently the harddrive being loose might be the issue, but the fact that this happened right after installing new codecs and running a disk cleanup makes that sound unlikely.

I do not have a boot disc as my OS came pre-installed on my computer, so I'm out of ideas. I went from some folders crashing my computer to not being able to boot it up at all

Sigh everything is just getting worse. I managed to get a startup disc from a friend but now my computer won't even get past the first screen. It doesn't progress past that "SAMSUNG" screen and pressing F2 which used to work now says "Please Wait..."Forever. At least before it went to the black screen and said "OS not found"

I'm totally lost and frustrated at the moment... If it is indeed a hard drive issue, what could fix it? Would I have to replace the harddrive? I'd rather not lose all my data as I don't have everything backed up. I'm a university student and have many notes from the past week that haven't been backed up and I need them for an essay due soon... Aaaarrrggghhhh...