Proper way to stop an in-progress Netflix movie?

Yesterday I started watching a movie on my TV using the Apple TV and Netflix. After a bit I decided to not continue watching, so I pressed the Play/Pause button, then was navigating through some menus (I've only had the ATV a few days) and later tried to stream some contents from iTunes. When I was trying to stream some video from my computer, the menu screen opened up not full-screen but about half-size and off to the side, and there was what looked like the image of a movie theater on the other side (flickering lights, a screen and people's heads). When I tried to stream the video the ATV had a lot of trouble - it stuttered and flickered a lot, this was new it had no issues before. I think I just didn't actually turn the movie off like I thought and the network couldn't handle playing a movie and streaming from my computer at the same time.

Q: what is the proper way to stop an in-progress Netflix movie? I go to their website and log in and get an option to 'resume' but not discard/cancel. I don't know that the Apple TV will work properly til it isn't trying to play a movie as well as whatever I'm asking at the time.

Q: if I get the same visual as I describe here (is this normal?) how would I navigate back to the movie? (the remote wouldn't let me do that)