Bill Cosby by far is the greatest of those mentioned and I would say the ONLY sane one of the entire group. Robin Williams has to OVER-act to be funny; Ricky really isn't funny in my opinion, Ellen used to be funny until she admitted just how "funny" she really is; Jerry Seinfeld has to feed an ego problem and is too damn cocky; And then there was this black lady that decided that Ellen's way of being "funny" was also good for her; and well Billy Crystal, how could you laugh at such a painful disguise of a so-called male comedian? Bill Cosby is the ONLY REAL human comedian and the others shouldn't even be listed. They fit more in the animal category.
It says a lot when you have an entertainer who can have everyone laughing without having every other word an "f-bomb", no blasphemy or crude sexual jokes. It is a rare talent and speak volumes about Bill Cosby's character.
I really wish there had been All of the Above. I remember Bill Cosby as Himself, and seriously nearly ruptured my spleen laughing when I saw that. But Robin Williams kills me, too. I have never heard of Ricky Gervais or Wanda Sykes, but Billy Crystal and Jerry Seinfeld are great, also. If you have never seen Bill Cosby as Himself, it is a DVD, and you should rent, buy or see it.
Of course, you should have added Peter Sellers, inarguably the funniest man to EVER live.
Robin Williams
Jim Carrey
Unbeatable stand ups.
R.I.P.
Wayne Brady
Steve Martin
Martin Short
The entire cast of MadTV
This is the funniest guy on the planet