I'm going to interpret this question as 'American Football or Soccer' not as 'one spelling of football versus another', just in case there were some varying interpretations.
I have a longstanding involvement with both football and soccer. I started playing the sport of soccer when I was eight years old, and played competitively in one form or another for most of my young life. I even went to Europe and played soccer there.
I started playing football when I was thirteen, and I played for only a few years. I had success in that sport as well, and I think I still hold a couple of yards per game and points scored per game records.
Soccer was the thing that I was best at. There are times when I wonder if it still is, and that I should have pursued it. Not that I would've been a great star, I never had the proper mentality, but there are lots of leagues in the world, and lots of ways to make a living. If it was the thing I was best at, maybe I should've pursued it for my career.
Football was a wonderful experience. The first time I realized I didn't have to kick the ball past someone to beat them, that I could just run around them, was a glorious moment. Football came easy to me, and I loved it.
The major difference in the sports for me was the way they were coached. I had soccer coaches of varying approaches and backgrounds and philosophies. Football is different. It's like the army, and your coaches are the drill sergeants. I had a football coach have to be held back by another once, because he was going to beat the shit out of me. The reason? I wouldn't tie my shoes up during warm up. I was fourteen, and he was over forty. Awesome.
Nowadays, I watch more soccer than football, and it is clearly my preference. It has always been my favorite sport, and probably always will be, despite how engaging both hockey and football can be. Soccer has an amazing, natural flow that you don't find in other sports. I love the strategies and the intensity of football, that's for sure, but I never settle into it the way I do with soccer. Football is strong coffee, whereas soccer is meaty stew on a cold, autumn day.
Food and drink analogies!
I just thought of something. If you read this, thinking of soccer as football, every time I say football in reference to American football, it probably confuses you.
Wow, this answer is pretty long. See, that's the problem with nostalgia sometimes, you start thinking about the good ol' days, and all those sports memories and before you know it, everyone in the room is asleep.
Short Answer: Football is the answer. Meaning soccer. Meaning fütball .