I've been playing Mass Effect 2 lately when I smoke. That's if I smoke by myself.
If I get high with my brother we usually play Skate 2/3 or I watch him play GTA4. That game is entertaining to watch, especially if the player is great at the game and knows the choice locations for shootouts with cops.
However, if you're around people who are fans and are familiar with the original Resident Evil, I highly recommend playing that. The bad dialogue adds nicely to pot humor/giggles. Also, dodging the zombies is lots of fun.
As for drinking, I used to play singstar with friends but I live in an apartment now so I don't bring it out, gets to be too loud.
Oh, I forgot another good one to play while high.
Daytona USA on the Saturn. The music is so damn awesome. "ROLLING STAAAAAAAAART!!!!"
and Panzer Dragoon Saga. So awesome, just flying around and exploring the towns. Love that game.