It's not my most 'favourite' kiss scene, since it wasn't really a proper kiss, but it's the closest Kakashi has ever gotten to a woman.....in that way {-_-} *sigh*
My favorite would have to be Yuuki and Yume's first kiss in Kanamemo.
http://www.youtube.com/watch?v=M0SS1JKgA70 (skip to 2:20)
Quick and sweet, and it establishes that they've been a couple since before the start of the show.
If I had a type it'd be you, fortunately I don't have a type so please stop.