HAHAHA JACK SPARROW IS AWESOME! Okay that was easy. Likewise you got Kurt for Glee and Arthur for Inception whom I've already fangirled so much about. And Blair, though sometimes I like Chuck better. But usually it's Blair because she's ~*awesome*~.
Sadly Vivian isn't my favourite character, if only because she only appeared once, and the other Captain Jack is only #3 in my list of Torchwood characters (not counting the pterodactyl who's about 100 times more awesome than any other human on the show).

Anyway. MERLIN!
My M/F OTP: Arthur/Vivian! And nobody tell me any different, it was a love written in the stars. I'm also partial to Gwen/Lancelot.
My M/M OTP: Arthur/Merlin. Need I say?
My F/F OTP: Morgana/Vivian. Have I already mentioned this theory of mine that Morgana was Vivian's true love and some day she's going to find her and kiss her and break the spell? There's like two scenes in which they're sitting next to each other. I call it PROOF.
My endgame OTP: Arthur/Merlin, with side Gwen/Lancelot (which at this point could be seen as a cheap excuse to get Gwen out of the way but I don't care, anything to get rid of the background violins).
My original OTP: Arthur/Merlin. I know, I'm boring.
My crack OTP: Morgana/Vivian is probably crack enough to deserve a mention.
My guilty pleasure OTP: Gwaine/Merlin or Arthur/Gwaine/Merlin. I usually like multishipping but with Merlin it feels like I'm cheating on my OTP. Haha.
My anti-OTP: Arthur/Gwen. I hope you'll understand me when I say, please, make the bad violins go away.