Katherine Heburn in Desk Set. It is an old movie that so few people under 50 have seen, but it is actually quite a good movie. It is the precurser to all of the Sex and the City generation books, shows , and films. The wardrobe is so clasic and elegant, wonderful.
As for more modern choices, I don't see much difference between a lot of movies. Clueless was fabulous, but I dont know if I actually loved the cltohes as much as I thought I did when I first saw it. I'll have to think more about it and repost.
matt