Could I have finally found the solution to my problem that has been plaguing me ever since I started messing around with MKV files? It seems that traversing around my filesystem, in folders that have an abundance of MKV files, my explorer.exe would crash, at least 66% of the time. I've tried disabling thumbnails for certain folders, and all folders. NO LUCK. I've tried installing the K-Lite Codec Pack that others have mentioned would fix this problem. NO LUCK. Today, I stumbled upon ShellExView, after someone mentioned that the DivX Thumbnail Provider was the culprit.

First attempt at opening one of my MKV folders was a success. Let's hope this persists. Thanks NirSoft!