In respect to this, can I watch an iTunes movie on a different computer?
All you have to do is visit the iTunes store and find the movie that you want, then pay and download it. You can rent movies from iTunes and watch them with your Mac or Windows computer, iPhone,iPad, video-enabled iPod, or on your TV using your Apple TV.
Similarly, can you download movies to Apple TV to watch offline? When you are ready to watch something, just tap it and then select the Play button with the app knowing where you left it last. On iOS, you can also download a movie or TV show from here, to your device, for offline-viewing. Just tap the download button after you select the TV show or movie.
In this manner, can I watch movies downloaded from iTunes on my TV?
Watch iTunes Movies on TV via Apple TV. If you already saved some movies in your iTunes library, simply choose Movies > Purchased (or Rental) on the Apple TV main menu. Then you can select a movie you would like to view on TV and choose Play to start playing the movie on your Apple TV.
Can you buy movies on iTunes and watch offline?
Once the download is complete you can watch it without an Internet connection. However, an Internet connection to the iTunes Store is required to authorize playback or activate the 24 hours time-limit of movie rentals. So, you can be offline and start the movie if it has been downloaded.