I've tried multiple different ROM's of Top Gear 3000 and I've encountered the same problem.... After I get passed the menu screens and it goes the racing screen it freezes up and gives me a distorted image. I can still hear the music though.
I don't think a released version of Snes9x fully supports this game yet. The game uses a special chip that has only recently been properly emulated (DSP-4).
The newer ZSNES builds should be able to handle this game since DSP-4 support was added. Pick up the latest WIP here: