I would guess that it goes:
Playing football
Playing Fifa
Watching football on TV
Watching football live
(with both playing options dropping lower, the older you get.)
When I worked in an english school, playing football was still hugely popular amoungst young boys and girls, and whilst they would also play fifa, not everyone had it.. and it was still (just) a second to actually playing outside.. Certianly not a distant second as it was when I was younger.. but a close second now.
There are a lot of young people who play football, but dont watch it.. but very few children/teenagers who watch football and dont ever play it.. so my guess would be that it would be as said above. Obviously live attendances fall behind tv viewing figures, so that stays bottom.