My tip: Avoid restaurants Downtown. They charge an arm and a leg and the food is mediocre. You can find some gems but often than not, I find if you get away from the city centre, you can usually get good food.
There is a Pacific Institute of Culinary Art in the heart of Downtown itself. It's no longer on Granville Island but there's a bakery by the institute there. If you want to try bakery, you can go there. If you're visiting Granville Island, I suggest you check out the soup bar there... there's chicken pot pie in a bowl. Delicious. DO NOT eat the fries and chips. Icky. Check out the brewery while you're there. They've got a tour of the place.
Chinatown is fantastic for Chinese food. Hons is pretty good. There's also one on Robson Street itself. Cheap and a lot of variety. If you want Malaysian or Thai, there is Tropika and Thai House on Robson Street. They have some lovely lunch specials.
Old Spagetti Factory in Gastown has got some good lunch menu combos. Avoid the Thai and Japanese restaurant there. YUCKOMETER.
For something special, you have to try out Gotham Steakhouse. Yes, it's downright pricey but if you want to hang with the right crowd and be seen (and maybe see some celebrities), it's the place to go. There's also the Keg.
Have fun!