Dome Gasket Shot?? Whats is a DOME GASKET???

the mechanic Said the Dome gasket was shot??? it looses anitfreeze so obviously some gasket is gone. Is the Dome gasket the HEAD GASKET??? and what trouble do i have to go through to change it cause i need the van for school next year, it's got 380,000kms on it, its the biggest LEMON van ever made but the engine runs fine, just damb gasket is shot and i need it for school, ITs and 3.8L Engine. i gotta fix alot of other stuff too like the back door latch, NO power windows work, Doors like to open when you hit bumps in the road, No heat in the winter, i'll change the heater core, I have to take half the dash apart (stupid General Motors Crap) anyways i gotta change the gasket before i go ahead on the other stuff. But I have to give it to GM the 3.8L engine is one hell of a good engine, lasts forever. So some help would be appretiated though with this gasket problem thanks!

The only gasket reputed to fail on the 3.8 - and that is not for all model year - is the intake manifold gasket, and that translates usually in coolant leak. SInce the intake manifold can be seen as a bulge on top of the engine, I wonder if this relates to "dome" in the mechanic vocabulary. It would figure.
check out this thread, on to 7th post:
http://www.automotiveforums.com/vbulletin/t206484.html
I understand the antifreeze "leaks", and does not vaporize from the radiator as frequent with the 3.1 head gasket problems, which also translates in inoperative heater....But head gasket failure with the 3.8 is unheard of on this forum and other 3.8 users (boneville, oldsmobile) in as far as I can remember. ANd Yes, the 3.8 is a hell of a good engine.