The car Mr. Turner jumps off on the skateboard is a 1998-2002 Volkswagen New Beetle.
When Mr. Turner screams like a girl while riding downhill on his scooter-turned-skateboard, his scream is provided by Tara Strong, who voices Timmy.
The following stores appeared in the background. Little is known about them:
Speed Racer - When Mr. Turner hears Timmy saying the car is being stolen, he deduces that Timmy must have hidden in the trunk of his car similar to the episode where Speed's little brother did the same thing.
Back to the Future - When Mr. Turner breaks off the handle bars to the scooter and starts skate boarding, it makes a reference to the movie.
Mission Impossible - When Timmy and Vicky are about to fall off the cliff, you can hear the Mission Impossible theme-like music.
It was never revealed with what Mr. Turner did with his old car. He apparently just left it in the middle of the street.
It is said that only people who can drive are allowed at the Dimmsdale Auto Show, but three kids on scooters are seen. However, later in the episode, Dad said he was lying to protect Timmy meaning that he didn't want Timmy to do some crazy stunt with one of the vehicles that would endanger his life.
If you look closely, when Mr. Turner screams and covers his eyes, Cosmo is briefly seen with buck teeth.
When Timmy is speaking Spanish, he calls Cosmo "Señor Cosmo" and Wanda "Señor Wanda". Señor means "Mister" so the right term for calling Wanda is "Señora Wanda", Señora means "Miss".
Right before Dimmadome says "Howdy!" (or right after Mr. Turner's new car drove off) Vicky's eyebrows are the same color as her hair. In the next scene it is black, as it should be.
Vicky and Doug Dimmadome adding 'Dimma-' to every word that starts with 'D'. (Dimma-Deal, Dimma-Don't; etc.)
(Mr. Turner is standing in the kitchen with his underwear, with Timmy)