I never liked YuGiOh, Digimon, or Beyblade.

^Yes:P

i hate Bleach all they ever do is fight. there really no meaning to that anime.

ps. love Kuroshitsuji

i had to pick this

Without a doubt my least favorite anime on that list.

Meh I find Naruto boring & I never really liked it =_=
my other choice would probably be:
Bleach (I have on & off -currently off- thing going on with this Anime/Manga)
or Sailor Moon (I kinda like it but yet...I kinda don't....)
or Megaman NT Warrior (when I first watched this Anime I remember not really liking it -_-)
or Yami No Matsuei (I watched this once *shrug* I didn't hate it but I didn't think it was that great either so....)
or either of the Yu-Gi-Oh choices (I don't mind Yu-Gi-Oh -I watch it every once & a while- but compared with some of the Anime's up there it would be one of my least favorites)

I can't comment on Junjou Romantica (I do know about this Anime but I just haven't seen it), Sekai-ichi Hatsukoi, Battle B-Daman, or Gakuen Heaven because I haven't actually watched them before so~.....(I've seen all the other Anime's up there though)