Not skinny, but not chubby/fat either... the guy in the picture you posted is too muscular to be considered average, in my opinion.
As for my preference, I'm not too picky. I like skinny guys, average guys (like the pictures I posted), guys who are a bit muscular, or guys who are a bit on the chubby side. I'm not really attracted to very muscular guys (like the pictures you posted for muscular and super muscular), or guys who are fat or obese. That said, I'd be willing to date a guy whose body type isn't my preference, since personality is far more important to me.
Average guys are descent, however, a little muscle around the arms are pretty attractive. Just saying. :)
Out of the above 5 links I prefer the 'average' one, though ideally I like my men to be bigger built than your example. Definitely don't like the skinny look or muscular/super muscular. I don't mind a bit of extra weight but ideally not as much as in your 'fat' link. Though to be honest, a great personality can make you attracted to someone no matter what they look like.