Just to state the obvious, different diets suit differebt people, but one that seems to work well for lots is the Eat Right for Your Type (see book of same name by Peter D'Adamo).
You need to know your blood type, then you eat the foods that are good for that group. Some people love it, need less sleep, the weight drops off, concentration improves, blood sugars even out so no going hypo, appetite falls etc. Other people don't want to give up the foods that don't suit their blood type.
And you won't lose weight without exercise, whatever the diet. It's not that running for x minutes burns y calories, but exercise changes the metabolic 'gear' in your body so you burn calories at a higher rate than if you lie on the sofa watching telly in your spare time. Exercise need only be a half hour walk a day, or house work or some other enjoyable indoor activity (now it's illegal out of doors)!
Good luck!