if you drive, there's this place by the sea... you eat literally beside the sea, tables are on the sand with candle lights.... it's by the safra country club at tanah merah. the restaurant is called shore restaurant. the food is not fantastic, pricing is like zu-chao. they serve western and chinese food. it's pretty romantic la... but some people might feel it's not very high class.
Can check out this website The Yummy Guide - Singapore Food Review Community for more ideas. I would recommend the Steffi's and Wine Company at Alexandra TechPark. You can find out more info from the website.