I'm more of a Dean fan...
It's mainly because I like his attitude towards things. He's quicker to pick up "fishy" situations. He seems to have the better "hunter" instincts.
I do like Sam too, I just prefer Dean...

and Castiel has to be my favorite angel.
c:
He's just so silly.

Definitely Dean for me. He's got a much stronger sense of conviction and loyalty and a very deeply rooted devotion to family, both blood and otherwise. And, he's just flat out badass! If I wanted to feel safe and protected, I'd choose Dean hands down.

Of course I love Castiel because we've seen much more of his character development than others. I don't like some of his choices/actions, but that's all part of his evolution.

Aside from Cas, I'd pick Gabriel. He's fun spirited with an affinity toward sarcasm (which I love), but he also has a strong responsibility to do what's right.

Sam