Yeah, my story is about the same as Kenny's. It was my first N64 game, and I think it's still my most well-used one. It's just fun to play. Here's the description I wrote the other day but the forums wouldn't let me post it:
It's a toned down flight simulator is the best way of describing it.
The controls are not overly complex, and FUN is the major selling point of the game. You get to choose a variety of vehicles, and you have to get your "license" for each of them. Getting your beginner's license is really easy, and is just there to get you familiar with the craft you are flying. The tests get progressively harder, until you are ripping your hair out trying to do them. The later ones require you to perform some quite hard feats.
Regardless of your aircraft type, or mission goal, when you land your craft, you are awarded a score based upon how well you did your mission. Common scoring methods include: Landing precision, Time on mission, Targets hit, Targets missed, etc.
If you have an N64, I would reccomend trying out Pilotwings 64. It remains one of my favorites on the system (and my oldest N64 game. I got it at launch), and I have actually gotten perfect scores on all tests no less than 3 times.
Just to give an example of a level in a Pilotwings game, I will describe "River Run" from Pilotwings 64 (my favorite level)
River Run begins on an airstrip in Little States, and you are in a Gyrocopter. The mission goal is to fly through all the rings that are floating in the sky. You take off and start flying through rings, and you fly over a boat, and over a hill, then it becomes apparent that you are supposed to fly straight down the Mississippi River. On the river are bridges, boats, and all kinds of stuff that you can run into. I have perfected it however, so that I can fly down the river at full speed, except for a single sharp corner. After you have flown down the river, you get ready to land in Miami, where a Space Shuttle is taking off from Cape Canaveral (sp?). As the shuttle goes out of sight, you land on the airstrip with a bit of a crosswind.