I'm reading the Omnivore's Dilemma right now, which is also an eye opener. It's very hard to eat ethically.
I do WW, but it's really just to keep myself aware. I don't stress about points so much as I want to make sure I'm not snacking and completely forgetting that I've snacked, you know? Like, if at work and I'm at my desk, trying to make a choice that will fill me up, rather than several smaller choices that don't.
But I do think it's good to be aware how bad some foods are - so it's handy for me to know that the general point values of foods in restaurants are. I typically eat more fish than meat, and opt for whole grains, so I'm usually on target with the healthier options, but every now and then, something sneaks by me and I'm shocked at the caloric/fat content!
That said, a woman I know says she just trys to eat food as close to it's natural state. Not like, freshly killed or anything like that, but as least processed as possible. I know I feel better when I opt for the freshly cooked meals over the frozen dinners, no matter if the frozen dinner is "lighter" or not.