my 01 ds 650 baja quit and oil is leaking out of the spark plug hole? help

 

You could have a blown top end.....but, check oil level, I'm guessing it's very high and could be because of a leaky carb needle valve and leaked fuel into the crankcase via the piston rings. Get oil to correct level, remove spark plug, spray some brake cleaner in the spark plug hole, and turn the engine over a dozen times or so....let it sit for a half hour, check the crankcase ventilation and ensure free and clear, install a new spark plug........and try to start it.