The cutest Poison type pokemon to me would be Grimer. I think it's absolutely adorable and I think that if it can supress its toxicity like OzzyCake suggests (and I think they do) then it seems like it'd be pretty cuddly, actually.
Fun fact: According to my mother who does not play video games, the cutest poison type pokemon is Gengar. In fact it's her favourite pokemon period.
As for the quiz... I am going to go out on a wild limb and say that the move iiiiiiis.... Poison Gas.