Just had a quick play anyway
It ran at a steady 60fps here but that's no surprise on my work PC.
I have a few suggestions:
1-When I hit a tree or boulder I assume that's game over? If that's the case it might be worth using something like "You Crashed!" or "Game Over!" as I wasn't sure if I would be able to continue if my car stopped spinning. Also the buggy seemed to speed up when I hit the obstacles which seemed odd. It should maybe bounce up into the air or slow down but not speed up.
2-It might be nice to simplify some of the textures like the police car and the buggy to match the simple style of the trees etc? I have some ideas for styling the general look of the game too and I'd be happy to talk via Email if you like.
3-I like the idea of getting drunk when you hit a bottle. Might be nice to give it some kind of text like "Don't drink and drive!". Also I thought some random 'wobblyness' might add to the effect.
4-Is there a goal or just last as long as you can? Might be nice to have a highscore table or at least a personal best to compare to?
Overall I think the game should work nicely on a netbook, the idea and gameplay are simple which is ideal. Also the models are low poly and there aren't too many of them on screen at any one time (are you using "exclude object" once an object is behind the camera or re-using the same objects? This could also help your fps)...
Fog might also be the problem here. You can get the same effect by playing with lighting and it should run a lot quicker.
Try using:
REM Put this at the start of your code
set ambient light 0
hide light 0
make light 1
set light range 1,500 `500 might be your current fog range
REM Then use this code in your loop
position light 1, camera position x(), camera position y(), camera position z()
EDIT: I just tried it on my netbook and yes I get around 10fps too. Have a try at using no fog and perhaps my other suggestions regarding objects and perhaps it will run a little faster.
