Sure, you need a functional MPEG2 codec. Media Player Classic can play MPEGs because it has one "built-in", so to speak. Here's one:
http://www.videohelp.com/tools?tool=Dscaler_5
I'm not up on WMP anymore, does version 10 not have an MPEG2 codec? Or maybe you do have one and it's corrupt? It might be wise to open an mpeg in GSpot to determine if you're simply missing the codec or if it's corrupt. Get the latest beta of GSpot here:
http://www.headbands.com/gspot/
Corrupt or "broken" codecs can be deleted using CodecSniper. Here:
http://www.videohelp.com/tools?tool=Codec_Sniper
Good luck.
