I think that the super-skinny jeans and ballet flats look is tremendously unattractive. Jeans that taper down to ankle width at the foot make girls' legs look shorter and stubbier than they really are, in my opinion. Jeans with a looser cuff at the bottom will fall a bit over the shoe, giving the impression of a longer leg (and thus, looking more attractive). A girl in jeans that fit snug around her midsection is hot, but if the jeans are tight all the way to her ankles, not so much.
As for ballet flats, I just plain don't think they're attractive.can't really explain why even.
I don't really care about the skinny jeans to be honest, but girls who wear flats are the best for me! I don't know how but it kinda turns me on :D strange. . .
Basically the opposite of the previous poster - I think ballet flats are the most attractive shoes on women, especially when they are very low cut. Tight jeans are great as long as they work with your figure. Different people like different things, though.
I am obsessed with ballet flats and I wear them mostly under skinnies or dresses but I have never gone past the limit to "SUPER-SKINNY SKINNY JEAN" - but I like this style, its very decent for me. The guys that I am usually around love it, but I am pretty sure there are guys who hate it. And, Lis4Loca is right, wear what you want to wear.