If you can convert the video it will remove it.
If you have trouble converting it try writing it to DVD, you could burn it and then rip it back again.
If its important (ie worth the hassle) and you can't find any other way, my fool proof method is to plug the my computers 'TV' out + audio out into my video camera, play it full screen on the pc and record it on the camera. Then I can resample it back to the pc..