I am also have this problem. However, I've not resolved it quite so easily.
I have consulted and followed the whole "read this before you post stupidly" thread and have taken most of the advice into account and downloaded stuff.
I have installed KLite codecs, that PowerDVD software, and a few others and I can't get the crappy video artifacting resolved. I've got a 64-bit Quad Core running Windows 7 (64-bit OS). I will continue to hunt.