The Dudeling (he’s 3.5) got wrapped up in a racing game at an arcade and extracted a promise to set one up for him at home. “Sure,” I said, dizzy with the screams and shouts of infinity-minus-one children.
I’d like to find something that’s about as realistic physics-wise as Pole Position or Night Rider—as in something that’s fun to play and easy to drive, not something with realism turned up to the point he won’t be able to make a single turn without spinning out. If it has varying levels of realism that would be great (I can always take it out for a spin). Clearly graphics don’t need to be fantabulous; as long as it matches late 90s arcade graphics, we’re set.
By toddler-friendly, I don’t mean it should have bunnies and kittens, I just mean relatively simple control-wise and otherwise straightfoward. He doesn’t need to beat any races or anything either; that can come later. I though about loading up GTA-IV, but accidents and pedestrian incidents might freak him out a little.
I have an old Logitech steering wheel and a middling computer (HP Touchsmart) to run it on. It should also be available on Steam so I can download/play it right away.
He’s staring at me right now. His eyes are glowing. Need. Answer. Fast.
Oh man, I can’t wait ro be in your position. Showing the kid the wonders of gaming. 
It’s hard to recommend a game that will absolutely run on your setup without a little more information. If you have the actual model of your PC, or if you know the type of GPU/CPU that would help.
Assuming they’ll run, I would recommend the dirt games. You can turn the difficulty all the way down and add assists which should help him keep the car on the track. Start with Dirt 2, it’s off-road racing, for the most part, so it should be a lot of fun for him.
Another possibility is trackmania. It’s a crazy racing game with crazy tracks. Very arcadey, lots of fun.
This is our kitchen so we were thinking form over gaming. It’s an HP 23" Touchsmart with a Core2 Duo 2.10GHz. Only 4GB RAM and an NVIDIA GeForce G200.
I forgot about Dirt 2. I got it a few years ago with another machine’s video card. I never got very far with it because I couldn’t figure out how to skip the hour and a half cut scenes. It’s easy enough to download/install, but I wonder if it’s graphics will be beyond this computer’s capabilities.
I wonder if I can just install MAME and Pole Position.
I f you’ve got an old Wii kicking around somewhere (or get one cheap) I’d say Mario Kart Wii is almost perfect. Kid friendly but surprisingly deep once you get into it.
I don’t really play racing games on the PC so can’t help with that.