Personal Experience
Soccer: Fairly easy even if you've never played before. You run up and down the field, you try and keep the ball away from the opposite team, try to find an opening, and kick the goddamn ball. The only thing that makes soccer remotely fun to watch, is waiting for that spanish announce guy to yell "GOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOAL!"
Hockey: Same concept... If you can skate, you can play Hockey. You have a stick, you smack the puck around, you keep it away from the other team, you try and score, but you're more likely to get into a fistfight with someone for no good reason.
Baseball: You have to have good reflexes, good hand-eye coordination, and good depth perception. You gotta know how to read a pitch, you gotta know how to swing a bat, and you gotta be able to throw straight and fast. Alot more skill involved.
Basketball: Similar to Soccer and Hockey, except for the fact that you have to continuously dribble the ball while avoiding other players, your goal is a foot wide, you have to THROW it through, and you don't have the luxury of tripping, kicking, or whacking your opponents with a stick. Skill involved.
I think the only reason that the World Cup is such a big fucking deal around the world is because EVERYBODY has a shot. Countries that don't have teams involved in any other sports have a shot at greatness! It's not because it's the most skillful game on the fucking planet. Personally, I'd rather watch a couple of guys beat the shit out of each other for a leather strap with some gold attached...