I vote for the tracks over the drags. From the participant point, more time on the track w/more skill required to win. For spectators, seeing "your" car or bike win is a hoot. That probably comes true for the drag spectator more than the circle track one.
I have attended both over the years & always felt like I enjoyed the track more than the strip.
The father of one of my friends owned an Indy car team going back into the 1950's & also ran sprint cars under various sanctions. They also campaigned midgets, and for my $, those things were the best bang for the buck. Dirt or asphalt, those things
Fly! Their history is fascinating, the well-heeled owners who could afford them ran Offenhausers, but eventually, other brands came into play, including 1/2-a-Chevy V8 Cesco's. VW's also had success. The Offenhauser cars are now worth big bucks especially if they have any racing success. The same builders who built Indy cars also built midget chassis, like Frank Kurtis, Edmonds, and Meyer & Drake, who eventually bought the Offy rights.
Many famous racers raced midgets, from AJ Foyt, Rodger Ward, Bill Vukovich, Parnelli Jones, to Tony Stewart.
Famous races where midgets proved their mettle against the finest and most expensive sports cars include the Monza, Italy Race of Champions, and Lime Rock Conneticut.
Here are some references:
http://speedstylemagazine.com/index.php?option=com_content&task=view&id=281&Itemid=31
http://www.conceptcarz.com/vehicle/default.aspx?carID=16823&eventID=275
Going over to your friend's garage and seeing an oval track car with freshly-marbelled tires sitting next to a couple of drums of methanol and a chemical safe for the nitromethane they added to the fuel for its power-enhancing effect has a way of making an impression. Seeing it run in anger makes an even bigger one, as I did from their pits.
Now I like to see the cars and bikes run at the strip, and walking the pits is fun too, but for me the bigger thrill is the oval, dirt or asphalt, and cars or bikes on it. At Daytona, my buddy and I always go to the flat track and have fun watching the bikes. I confess I enjoyed it more when they ran the H-D 750's along with all the other manufacturers, but there is a variety of engines now competing, and the guys who do it are very skilled.