Adding Genre to Movies

I upgraded my apple tv last night to the latest and greatest firmware. I noticed the new sort be genre tab under my movies but the only the movies I have purchased sort out in to genre. all of the others are under Unknown. So I went to Itunes and added the genre in on the info page. But it is still not sorting out on Apple TV. I also saw that there is some new parental controls, such as allowing nothing more graphic than PG. Where is that rating info stored? I have converted many movies and would like to add that info in. Would like to keep my 4 year old from watching scarface again.