I did weight watchers a few years ago and lost 3 stone but slowly put it back on again. I'm now on a vegan diet as I can do this with the diabetes and I find it's much easier than counting points or calories. It's basically super healthy, low fat, low cholestorol and there are a lot of yummy recipes online - although I do cheat a bit and sometimes eat quorn products which strict vegans aren't allowed, but it's a diet to lose weight, not a lifestyle choice so I'm not bothered really! I haven't missed meat or even cheese, although struggling slightly without fish or eggs! It's really not as extreme as everyone seems to believe though.
You must do some exercise with it too, it will get that fat shifted much faster and you'll feel so much better after doing it. Plus it will help to keep the weight off after the diet - my biggest problem was leading a sedentary lifestyle which I've now fixed doing regular aqua classes and a weekly gym session.
I feel so much better on this diet and with the exercise, which isn't full-on or scary, I can highly recommend it.
Good luck.