Hello, Heidi. I have some good news and some not so good news for you.
The good news is that you can convert any audio/video format to any other audio/video format if you have the correct tools and codecs for such a task.
Unfortunately, however Switch doesn't deal with video codecs and formats, only with audio so it can't help you with this problem.
I would recommend Ulead VideoStudio for video format conversions, it's also a very powerful video editor. You could try downloading the Free Trial and see if you can do something with it that meets your needs.
I'm assuming overall that you need to convert an ASF video file to an MPG or MPEG file, right? This movie editor can do that very easily. Take care and good luck, post back here if there's anything more I might be able to help you with.