Well as far as 'free-range' goes, that just really means they aren't in cages. They are usually cramped indoors and never see sun light or touch grass but that is definitely better than the cages. I looked into pasture raised chicken eggs for my dogs because I have some difficulty with one of my dogs. When I did, I was shocked how even pasture raised can mean a bunch of chickens in a fairly small shared cage but they have grass under their feet instead of concrete. The pasture raised chicken eggs I buy for my dogs is from a farm not too far from me and the chickens do have a fair amount of space.
I think there is a lot of good information out there and I have to say that I went vegan for health reasons. I read about cancer rates, diabetes, heart disease, etc. From reading all that, I think dairy is actually one of the worst things you can eat. In terms of animal treatment, dairy is also one of the worst industries in how animals are treated. Eggs are probably the best in terms of animal products and health and you can find farms moving towards more humane treatment of egg laying chickens.
I initially started going toward vegetarianism because as I started to eat better, I started to lose my taste for meat. It was such a strange thing because I used to love meat. I then read The China Study and other information about vegetarian/vegan diets. I think Eat to Live is a good book to read and it gives recommendations on what animal products to eat if you are going to eat them.
Anyway, I was headed down the path of being a very cheesy vegetarian and with no thoughts of being vegan but I was convinced dairy wasn't healthy and gave it up and meat and eggs all in the same day. I even had steak the night before as I really didn't think the change would happen so quickly for me. I did have a couple relapses, specifically when I went out of the country on an already planned trip. I just didn't feel good and the foods didn't taste good to me anymore.
I have to say I love the food I eat now. I cook a lot more and enjoy cooking a lot more. It is funny when I pull out my lunch and want to clap because I'm so excited (uhh yes, I'm strange).
Lastly I will say this as I know it is a touchy subject and it is hard for me to tell people this. If you have cancer or are at risk of cancer, there have been people who have successfully fought cancer. There are also some amazing stories I've read about people who had cancer, went vegan and miraculously recovered. I take stories with a bit of a grain of salt because I've never known anyone personally but I think it is possible if you are feeding your body 'bad stuff', then your body can't heal yourself. If you are eating lots and lots of veggies, whole grains, legumes and fruit, then I think it can fight diseases.
Oh and I highly recommend a visit to Sipz on Clairmont Mesa Blvd