Yes, exercise will speed up fat loss. You're doing pretty well already, but you will keep your metabolic rate up if you exercise as well as doing good things for your heart etc. Metabolic rate can slow down when we diet, whatever sort of dieting we do, (though low fat, low calorie diets are worse in this respect) and that can slow down your rate of loss eventually. It's like your body susses that times are hard and its not being fed a lot, so it slows down the rate at which you burn food to conserve it - not what we're after!
IMHO a mixture of cardio and weights is the best - whatever cardio you like 3-5 times a week and some weights 2-3 times maybe, or if not the gym, at least sit ups, step ups and push ups.
The cardio is what's good for your heart and helps raise your metabolism.
The resistance stuff builds muscle, which also helps raise your metabolism.
You may actually slow the
weight loss a bit since the muscle you will be building will weigh more than the fat you are losing. But - you will speed up the process of becoming thinner - always a good thing!
Good luck with finding a program you enjoy,
Jay