My dad and I flew over to Spencer, Iowa (KSPW) a few years ago and went golfing. There's nothing special about the airport, but the courtesy car and golf course were nice.
Also, Boone, Iowa (KBNW) is a funny little place. There's not much there except an old retired police cruiser for a courtesy car. My old instructor and I had fun shining the search light at people as we drove to and from lunch one day. This was two years ago, so who knows if it's still there or not.
I did my private license at Cedar Rapids (KCID) and it's a friendly place if you want a bigger, Class C type of airport. Funny thing is, I didn't even know they have a restaurant there...maybe Amber is right, maybe it's good.
You could also check out the suggestions people have given me in this thread:
http://forums.jetcareers.com/showthread.php?t=37118
And you know, now that I think about it, I'm not sure if any airport in Iowa is really that amazing...the good times I've had here have been more a function of the people I'm with and the things we've done at the destination once we got there. So I'd say to grab a good friend, fly to any random airport, and see what you find...you'll make some memories, one way or another.