Simpsons is hit or miss, for me. And not the entire episodes -- though there are some classics. Usually, though, it's a few choice gems in a given episode, surrounded by a hefty dose of so-so humor. South Park has me laughing more consistently.
I've not yet developed the intelligence for King of the Hill, Futurama, or Family Guy. And probably won't, since I don't try.
Bill Murray is a favorite.
I mentioned those female comedians on another thread, but I'll mention them again: Ellen Degeneres, Paula Poundstone, Rita Rudner.
Oh, and Steven Wright.