I haven't seen any of the races here, but I took my son to the Fireman's Park on the grounds of the Speedway. The playground is any kid's playground fantasy come true. The ground looks like it is made of tanbark, but turns out to be recycled tires, making minor spills nothing to the kids. The park is split into two playgrounds: one for little kids with swings, a sandbox, and steps just the right size for kids around the age of 1 - 3. Then there's a bigger playground for the older kids. A tire swing, huge slides, and a outdoor musical instruments were the highlights for my little guy.
The only problem I had was that some of the kids had an attitude toward me or my son... but then again, that isn't the playground's fault, but the parents.