If you want to drink alcoholic drinks, then your choice of restaurants is limited to hotel ones, of which there are plenty, but they're expensive. For instance, last week a bowl of mussels, a plate of meatballs, 2 beers and a glass of wine at the Belgian Beer Cafe [1] (Intercontinental hotel: nice place with outdoor seating and live music on Fridays) cost me about 500 dhs. Also last week, one shared starter and two main courses, together with 3 glasses of wine at Certo (don't even think of going - it's awful) cost me 380 dhs.
If you're not bothered about alcohol, then the city offers you a gazillion local restaurants, serving mostly the indian, pakistani and lebanese expatriate community, where you can eat a full meal for 30-50 dhs. One good place you could try is the Lebanese Flower, which is a touch more expensive (50-90 dhs). There's a branch [2] near Al Wahda mall on 11th (any taxi driver will know where it is, but it's 10 minutes from the Corniche) with outdoor seating and the chance to witness countless Emiratis rock up in their LandCruisers and honk the horn for drive-through shawarmas. There's another branch somewhere in Khalidiyah which I've never been to.
Or you could try Vasco's [3] at the Hilton Beach Club, which is on the Corniche and has a good mix of food but is hotel-based so more expensive.
Or for good local flavour combined with great views, try Le Boulanger [4] (lebanese food) on the Marina Causeway: if you can find a spare table outside it's well worth it.
For swank with service, Hakkasan in the Emirates Palace is excellent if pricey. [5]
For a cracking but expensive Indian, there's Ushna at the Souk [6], or the excellent, pricey and sadly often empty Bord Eau at the Shangri La [7]
[1]
http://www.openstreetmap.org/?lat=24...om=18&layers=M
[2]
http://www.openstreetmap.org/?lat=24...om=18&layers=M
[3]
http://www.openstreetmap.org/?lat=24...om=18&layers=M
[4]
http://www.openstreetmap.org/?lat=24...om=18&layers=M
[5]
http://www.openstreetmap.org/?lat=24...om=17&layers=M
[6]
http://www.openstreetmap.org/?lat=24...om=18&layers=M
[7]
http://www.openstreetmap.org/?lat=24...om=18&layers=M
Hope that helps!