You missed the first sentence of my 3rd reply.............I wrote : You have Windows Live Movie Maker.
No, you do not need to uninstall your Windows Live Movie Maker.
You can have both in the same machine. ( I have both in my Win 8.1 Pro 64-bit ).
As far as "compression" goes, it is really not a good idea. The result of severe compression would distort the quality of the video.
Which is also the reason I asked why would you want to do that. It's not necessary in my opinion.
But then, I am not a fanatic in movie making and such. I rarely make videos.