If I want to watch a movie in 1080p resolution on a 720p screen is the image going to be better than watching a 720p resolution movie on the same screen?

If I want to watch a movie in 1080p resolution on a 720p screen is the image going to be better than watching a 720p resolution movie on the same screen? What if I play video games in 1080p- would they look better than if they were played in 720p?