Lesson 1: Diets are not a good idea
and lesson 2: There is no such thing as spot fat reducing.
To clarify, a diet is something you pick up to lose weight, there are usually quite strict and not very fun.
Once you get the weight off you stop with your diet, and go back to the old habits that got the fat on in the first place, so that means you need to create a lifestyle which includes more activity and less unhealthy foods.
And you cannot just lose fat on your stomach by doing crunches or anything, your body decides where it pulls the energy from, and the stomach fat is usually last in line.
Also the reason why lovehandles are a big source of frustration since it's the first to come and last to go.
With that being said, any workout will do, you just have to burn calories one way or another, so I would suggest picking out something you enjoy doing, and set up a routine which you will be able to follow and keep up with, don't make it too easy on yourself but also not too hard, which would make you more likely to give up on it.
If you go about it half-assed, you will get results that reflect that.