Ooh, a quiz!
Which episode of the entire series do you believe is the best?
Oh geez, do I really have to choose? Well, if I don't count the specials...I think I'll go with "Room With A Feud," though there are many other awesome episodes. I was laughing all the way through, and I enjoyed seeing Wilt actually stick up for himself for once. XD Keep in mind I haven't seen all of the eps yet, though, so my opinion may end up changing. XP
Which episode of the first season do you believe is the best?
"Who Let The Dogs In?" was a good ep in my book, those puppies were so cute. :3
Which episode of the second season do you believe is the best?
"Frankie My Dear."
Which episode of the third season do you believe is the best?
Here, I'd say it's a three-way tie between "Room With A Feud," "Setting A President," and "One False Movie." I already mentioned RWAF. I loved how "Setting a President" showed a slightly more human side to Mr. Herriman, plus it had Frankie and Frankie is cool.

And Bloo's crazy movie was totally what made the entire episode in "One False Movie." XDD MOVIE STAR WILT FTW.
Which episode of the fourth season do you believe is the best?
Tie between "Bus The Two Of Us" and "The Big Picture." I loved Wilt's freaking out and Goo's ridiculous versions of Mac, Bloo and Mr. Herriman in "Bus The Two Of Us," and the rather intriguing mystery in "The Big Picture." :3
Which episode of the fifth season do you believe is the best?
"Schlock Star" and "Bloo Superdude." (Man, I just can't bring myself to pick only one ep. XD) I'm always a sucker for the concert stuff, and I was laughing so hard my sides hurt when I first watched "Bloo Superdude." Now THAT was some hilarious craziness. XD
Which of the five seasons do you believe is the best?
...I can't choose. ;;
Which of the special episodes do you believe is the best?
Good Wilt Hunting, without a doubt! A movie all about the Wilt-man was exactly what he needed.

And it was played off so well! I would definitely choose this one as my favorite ep of all, if it counts as an episode.
Which of the shorts do you believe is the best?
Er, I've only watched, like, three of them...I don't think that's enough to make a judgement.
Which human character do you believe is the best?
Frankie! She's my second favorite character in the show.
Which Imaginary Friend do you believe is the best?
Wilt! He's without a doubt my favorite character.

He's sweet, always putting others before himself, and is a good role model. x3 Plus I can relate to him in some ways.
Which ?minor?, or background character, do you believe is the best?
Beeerrry.

Gotta love the psychotic squirrel thing!