There's no way to target fat loss to a specific area of the body, so all the ab exercises in the world won't help flatten your belly. The best way to lose fat is through a healthy diet and regular exercise. Your body will decide for itself where it wants to take the weight off, and eventually it should come from those areas where you carry excess.
I don't know if planks would be an option for you (I'd suggest asking your doctor because of your neck problems), but they are a great core exercise: www.sparkpeople.com/resource/exercises.asp
But again, you'd want to do those in combination with a well-balanced strength and cardio program.
Hope that helps,