i think straight or slightly wavy hair is hotter in general. overly curly hair draws attention away from the face and I think most girls who suddenly iron their hair one day when it is usually curly look prettier and more feminine.
but if the hair is wavy and not puffy it looks nice. I like hair that is straight or slightly wavy but not pin straight like avril lavigne, that is too flat.
Straight hair is generally preferred, with curly hair generally being the least preferred. It's nothing personal, it's just that straight is easier to manage, run their fingers through and most girls with straight hair don't have that "don't touch my hair" complex.
I have curly hair & while I may not have guys running to me, I certainly haven't had a problem. It's just not preferred