To watch: Figure skating/gymnastics/diving - anything GRACEFUL and that includes judges giving points
As for those non-judged events, I'd say SWIMMING because it's fast-paced, exciting, and includes people like Michael Phelps in speedos.
To do: Running - it's even simpler than hockey, cheap, and calorie-burning, so it's good for a healthy lifestyle. All you need is ground, running shoes, and a heart that's beating. I can't wait until track starts...been eating too much lately that my size 00's feel tight.
Swimming is a close second. It's almost better since you don't get gross and sweaty, but it's less strenous and you can't wear headphones and feel nearly as pumped.
I tend to like all individual sports - to me exercise is a solitary activity. Well, two-player sports like tennis are fun too, but I dislike team sports.