Earl and Randy from My Name is Earl.
I second Cliff from Cheers.
Dwight from The Office.
Shark Boy (the TNA wrestler, not the kid movie character).
And I could see Cliff and Randy getting in an awesome conversation:
Randy: Wow, we're lost on a desert island. That's pretty cool.
Cliff: Did you know the Romans invented desert islands?
Randy: I think it would be cool to be a Roman. They get to see real gladiator fights. I've never seen a gladiator fight. I saw American Gladiators before, but they didn't actually fight.
Cliff: Pygmies from South America actually started American Gladiators. They'd sacrifice the winner to the anaconda.