Ralph Lauren Romance, perhaps?
You do want something with a bit of gravitas to it, given the occasion. But as you are 17? 18? 19? I wouldn't go with an older powerhouse fragrance like Shalimar or the ilk......before I sound hoary and old on you I'm 26 and still don't have it to carry some of those off. Allure is also a good choice. I would stay away from things like Curve or Ralph Hot/Cool, etc, essentially the "fresh" fragrances so heavily marketed to our age group. Above all, wear what makes you feel like the princess you will be that night. have a wonderful time, and cherish your memories.