Meh. Black over white (not a fan of lace). I'm a fan of more classical styles, but as long as it's not a tube/strapless it's not a deal-breaker. Just make sure you have the body for it. Those side-slits on the black will be pretty unforgiving.
cant see the first one because its out of stock which is causing an error. but from the sounds of it, it was a white dress compared to the second one which is black. id have to know what you look like to really give you an idea. and no descriptions since 5'8" skinny girl could be anybody. as far as the dresses are concerned though, I'm not a big fan of them (the one shoulder kind). its w/e though. dress the way you want to dress. :)