Where does the Windows 8 "Video" app download to on disk?

First allow me to admit I am fairly new to Windows 8 (as I am sure most are) but have been a Windows junkie since the early 90's so have been quite satisfied with the "user-friendliness" level of the operating system so far. Lately, I have been using the "Video" app quite frequently since it has been my primary source of movies and TV shows over the years through my XBOX 360. Now when I purchase a particular movie or TV episode/series, I am usually given a notice that the movie/show will not be available for download or stream after a particular date. Now this is OK for some titles (especially TV shows that I rarely watch more than once) however for most, I prefer to download them so I may have them forever. My XBOX hard drive is only 250 GB so the space obviously will not last forever so it seems only logical to download them on my PC since I have far more space not to mention my two networked 1 TB backup drives. Do the movies download to a folder on my PC where I can back them up or store them if say I would like to watch them again in the future on my XBOX via Windows Media Center? Or is it proprietary to the extent that they are downloaded as somewhere in my appdata folder(s) with strange extensions that cannot be played except through the "Video" app on this PC alone? I thank anyone and all who are able to assist me with this issue in advance and appreciate the help as well!

Robert D Droege