wow you run a fast computer. I converted a 348 MB .avi file(Heroes episode) to .wmv (according to the software at 768kbps). it took me about 30 mins and BTW my computer is stone age compared to what you've put up.
i dont know if thats what your looking for.
the software is AVS video converter.
here's the link: DOWNLOAD LINK
you can thank Putis or Yensed..i forgot which one had it posted.