what to wear, what to wear???

so for my 28th birthday, we're hosting a "90's" themed party. costumes are strongly encouraged of course! I'm at a fork in the road right now....which way to go, which way? I have 2 complete outfits picked out & a jacket picked out to make a complete outfit. I'm going for the whole Alicia Silverstone ala Cher Horowitz in Clueless circa 1995 :)

here are the choices:

who doesn't love a good 'ol jumper?? maybe with brown knee high socks?

this is the incomplete outfit choice, what should the lower half of my body wear?

this one is very librarian, I think. LOVE the shoes! :) maybe w/ cream colored knee high socks?

what to wear, what to wear??????