What is the best video converter to use?

Windows Movie Maker doesn't let me put videos from my digi cam because it's in the wrong format so what converter can I use?
I want one that's pretty decent quality, doesn't cost anything, doesn't stick the logo on my videos and it converts all of the video, not just half of it.
I used to have prism something but then my trial run ran out so yeah, I can't use that >.<
And zamzar has a limit of 100MB :l

Help please?

u can use total video converter!

I recently got one Sony HDR-XR200V Camcorder I want to convert the files from m2ts to MKV I have SONY Vegas but MKV Vegas isn't there. I basically want to convert m2ts file into a more common video formats, how to do?