I haven't done an ironman - not sure I want to, but I'm intrigued by the half.
But I like race day. Even for the marathon or the long cycling days. I've only done olympic distance tri's, so that's hard to compare.
But for me, the reality is that I don't think I'd get out and exercise as much as I do if I didn't have a race of some sort I was looking forward to. And I really do enjoy MOST races MOST of the time. Yeah - it isn't without some discomfort. But the discomfort is easy to ignore as I see my pace and see that I'm ahead of the year before, or see the people I'm passing. Or just marvel at the fact that I'm doing what I'm doing.
I think saying races are fun is a good description. Different kind of fun than going to the beach or Disneyland. But fun nonetheless.