Hey wumply,no problem the filetypes in WMP11 are as follows,

Windows Media File(asf)
Windows Media Audio File(wma)
Windows Media Video File(wmv)
DVD Video
Music CD Playback
Windows Video File(avi)
Windows Audio File(wav)
Movie File(mpeg)
MP3 Audio(mp3)
Midi File(midi)
Aiff File(aiff)
AU Audio File(au)
Microsoft Recorded TV Show(dvr-ms)

And thats all,maybe im mistaken but wasn't there more file types in version 10?

Also for reference i have ACE Mega Codec Pack installed,latest version complete professional install.So i doubt it would be a lack of correct codec issue in my case.