The easiest way to convert WMV to anything is to use
TMPGEnc to convert to MPG and then you can open MPG in just about any video editing software and export accordingly.
My computer at work is rebooting every 30 minutes (I hate PCs) so I wasn't able to use the legacy version of TMPGEnc which does a perfect conversion. Newer versions of the software sacrifice quality for speed. I was about to make an MPG on this dumb lump of a PC that's 162MBs with great sound quality but a slightly skewed aspect ratio and the last 3 seconds of the clip cut.
If any of you with your sexy working PCs can get around to it you can get the older version of TMPGEnc here:
http://www.dtheatre.com/pow/tmpg/ Install
tmpg_jp0725.zip first. If you read Japanese you are set, else install the patch:
tmpg_en0725.zip.
If not, I've got the MPG up on my web server so I can access it over the weekend. I'll try to take it to my Mac and make love to it with Final Cut Pro and fix the aspect ratio tomorrow. Assuming I live through my bike race and planned after-partying tonight. Booyakasha!