GE Force 6600 - NV_disp.dll error

Using a GE Force 6600 with newest drivers from Nvidia ( 81.85 ).
When I try and play any type of video file (mpegs, AVI's etc ) Windows Media
Player seems to hang and then after about 20/30 seconds I get the "BSOD"
with a message that Windows stopped to avoid any damage to my system and
that driver NV_disp.dll got stuck in an infinite loop.

I've tried removing the drivers and doing a clean instal, but still the
same.

Out of interest, I have found a couple of "minidump" files that co-incide
with these crashes but have no idea how to use them. Do these give more
info about the problem ?

Thanks
Andrew