I did actually try to get into American Football once, I am a sports junkie and thought, why not give it a try. I watched one full game, the last 2 minutes lasted about 40 minutes, gave up.
About 2 years later I decided to give it another go, it was Thanksgiving so turned over to Sky Sports to see what was going on. I turned over to Nickelback playing in the middle of the pitch, they were just finishing, so it stayed on but the 2nd half was delayed because they had issues with getting the large stage off the pitch, that is when it went off and stayed off.
I would recommend watching Redzone at first.
It's a great watch , will help understand the game and focus on all the exciting moments of games.