I agree that diets usually won't work in the long run, because its hard for people to follow them for a long period of time (=the rest of their lives).
So, what I believe in is general guidelines and a life style change.
I compete in strength sports and take my training and physique very seriously. I don't have six pack abs (yet), but I'm not too far away (a six pack is barely starting to take shape, so to speak

).
I'm not saying that I'm any type of "guru", nor a body builder, but I managed to change my physique from overweight powerlifter to a 65lbs lighter strongman without noticeable loss in strength (meaning most of the lost body weight was fat). I did this in about 18 months.
As mentioned previously in this post, you need to balance your fat, protein and carbs. Most people get way to much carbohydrates. Also, and this is very important, carbohydrates increases your production of insulin. Insulin is a hormone that helps the body convert proteins into muscles, but also to store fat. This means that if you drink a coke while eating a hamburger, you'll get a much bigger spare tire around your waist than you would if you took these two items separately.
The types of food I eat a lot of are:
1) Meat. All types - and lots of it. Lean meat is of course the best.
2) Sea food. To be honest I hate sea food and hardly ever eat it, but if you like sea food, go for it. The fat you find in fish is healthy, but watch those calories. A gram of fat contains more than twice as many calories than a gram of protein or carbohydrates.
3) Nuts. I snack on nuts with protein shakes almost every day. It tastes great and is very healthy. A lot of calories though, so you should control your intake if you don't work out rigorously.
4) Oat meal. Great for breakfast. Slow carbs and lots of nutrition.
5) Brown rice. This is what goes with your meat/sea food. Not potatoes, definitely not white bread or pasta.
6) Fruit and vegetables. Goes without saying. A fruit smoothie while working out works great for me. I just throw everything I can find in it: strawberries, blue berries, apple juice and some protein powder. Maybe some bananas etc.
7) Milk. You can get bloated if you drink too much, but skimmed milk has a great nutritional value. I drink about 1 liter a day, which seems to be a good amount for me.

Candy. Yup - I eat it, but only once a week. If you work out very hard you'll deplete the glycogene in your body. So-called "carbo-loading" will replenish it. If you don't work out extensively, you probably don't need to carbo load, but having one day a week where you enjoy a pizza doesn't mean you've ruined everything. Enjoy yourself, but in moderation.
The most important to do if you want to lose weight is to WORK OUT.
Get an elliptical machine and do an hour at least three times a week. Get a pulse watch and try to keep your pulse at around 70% if you can.
Good luck!