I have two favourites; L'Air du temps by Nina Ricci and Stella by Stella McCartney. Right now, I hate Ricci, and think the smell is too sweet. So I wear Stella, which I love right now, but after a month or so I have to change the fragrance,because it starts to smell awful, too strong.then after awhile I'll switch back to Stella and then back to L'Air du Temps and so on...So I have this kind of love-hate "relationship" to them.
I once got 1947 by Dior as a birthday present.Smells awful. I gave it to my friend.
I dislike too heavy fragrances, and in my opinion, the most awful scent ever is Opium by Yves Saint Laurent.Though the ad campaign is lovely.