How to display a specific category in the front page

I am using the TV Theme to display a set of videos that I have clasified with different categories, I want to display in the front page by categories instead of date or popularity.

I tried several query strings like

cat_id=7&posts_per_page=4
cat=7&posts_per_page=4
category=Test&posts_per_page=4
cat_name=Test&posts_per_page=4
category_name=Test&posts_per_page=4

None of the them works, some do not display at all others display all the videos in any category

What is the rigth way to do it?

Thanks for the help