personally suggest "Seasons in the Park" at the peak of QE park. you can see the downtown from an elevated area. Food is good too. It hosted a variety of events including a dinner for Presidents Boris Yeltsin and Bill Clinton during the 1993 Vancouver Summit, the wedding reception for Vancouver’s singer/songwriter Sarah McLachlan.
The other suggestion is Le Gavroche. French cuisine. It is in a refurbished Victorian styled house. Good food and very relaxing and romantic.
I would have suggested Lumiere or West but both restaurant's head chefs are leaving (not sure if they left already) I am not sure if they can retain their quality. If you are looking into fine dine (expect to dress at least smart casual for that), you can try tasting menu at C (regular menu isn't so good... IMO).
Fuel has pretty good food but it's less formal and the room isn't very romantically set. Haven't go fine dine for a while.. not sure any more