Apple Tv question

[onetoescape]

More questions about Apple TV! I am considering going down this route but have some questions. After buying the Simpsons movie for what feels like the 5th time I don't think DVDs or BluRay work in house. 4 kids fighting over which movies they want to watch and then because of the fights the discs get scraped. I am thinking of going down this route and buying a couple apple tvs. First up if I get 2 or 3 of these is the media locked down? Can they have 3 separate Simpson movies running at the same time? If I start buying the movies / tv shows this way are there any limits? By this I mean the apple tv box only seems to have a relatively small hard disc space. Is it easy to delete stuff of this? Or how does the process work? Is it as long the main itunes library has the videos it is ok? Can I lock it down so that they can't view material I don't want them to see? Lots and lots of questions