i moved out to south lake tahoe this winter so i haven't been around mt snow so i'm not sure what the trails are like but pretty much grommet is usually the xs park with a bunch of smaller ride on boxes and rails, possibly a small urban sometimes. nitro is a good medium park that can have features that are both on the smaller and bigger side, then like cheese said if you stay right when it forks that turns into a small medium park.
as for food if you're talking about a place to get shit to cook you'd be better off going to snow mtn market thats down route 100 from Mt Snow going towards wilmington, its maybe a min tops on your right hand side after you pull out of the mt snow entrance. in the same area there's a snowboard shop called invasion which you should check out as well, my friend pete owns that place and is super cool.
a couple bars around the area the people like to go to are dover bar and grill(or D-BAGs as people call it) which also happens to be in the same area as the snow mtn market and invasion, across the street from there is a bar/restaurant called The Silo, then down 100 about 2 miles from there on your right is a place called The Saloon that has some decent food and a bar with pool table.