Mann this is a subject close to home. I havent read through the whole thread I did get quite a giggle on some of the posts....
Here is my two cents from a person who had the crap scared out of her in the sixties.
First and foremost Get a copy of the Foxfire books. When I had my first copy there were only four i believe there are over thirty now. If the power grid goes down we all need to be able to rely on reference information that is easily accessible. They cover everything from soap making to wheel wrighting.
Animals to raise:
It really depends on how you are going to feed them. I live in the desert so free ranging without food supplimentation is a no go. The wells here are five hundred feet or more deep so pumping water with a windmill is out of the question (standard windmills are limited to about 250 feet I believe) So I will have to convert the well pump to Solar power, at the very least.
If you are going to live off the grid on land that has ample accessible water and perminant pasture and provided there is no world wide collapse Here is what I would have
Chickens
Goats .... Dairy goats just like cows have to have a baby in order to provide milk therefore you will have to have a Billy or access to one. But a single goat can produce enough milk to supply the family in dairy. They have to be milked twice a day. They are good foragers and have very few health issues. There are some goats that also will provide fiber for weaving. Goats are also more sociable than sheep are. Sheep revert to their wild nature a little too quickly for me. though I would love some Barbados.
Rabbits are good. My grandpa was a sharecropper and he used to raise them in a large pen when they lived in Texas. Fenced off about an acre with fencing dug in about thirty inches deep. They provided shade food and water and the rabbits provided their own housing by by tunneling. Dad said the pen looked almost empty during the hot part of the day. But come feeding time They would come out of their holes for chow. He said they could raise a couple hundred in there.
You can do horses. I spent the last 44 years with horses. There are lots of very hearty dual purpose breeds out there. Some have mentioned Morgans Arabs I am sure others. The hot breeds tend to need more calories to be healthy colder breeds are good too. I have a 2000 lb Percheron mare. Surprisingly she eats no more than a Light horse that may weigh half her weight. (feed measured out in calories) Unless you are experienced with horses I would wait until I got an education with an experienced well rounded instructor to teach you horse husbantry. I do carriage driving and have done some work with horses in harness. This is something you should NOT attempt till you are trained in all other aspect of horses and have a horse that is already trained for this type of work. It takes approximately two years to be come an intermediate novice in my opinion.
For horses for working on the land and for riding to town or other transportation Fijord is a good choice. They are considered Draft Ponies because of their height and stature. A team of Fijords can do most of the tilling and cultivating for crops and harvesting hay. For driving to town they have an incredible mile eating gait. And realize a thirty mile trip will take you two days. One there and one back and only with animals that are fit for the task. Say to get supplies with a wagon.
For working the farm Oxen are also a good choice. Though again working with Oxen takes training and husbandry classes this kind of training is not as easy to find as horse training is. But Oxen are incredibly strong Much stronger than horses. For those who dont know an Ox is simply a Steer that has been allowed to mature, they dont technically become an Ox till their fourth year. I have seen a team of Dairy Cow Oxen over 15 hands tall.
Here is an article from Rural Heritage Website, just like BYC but for farming with animals and an excellent place to connect with people living the off the grid lifestyle. Some farm and log with horses some are hobbiests. Its an extensive site I highly recommend it.
http://www.ruralheritage.com/logging_camp/ox_vs_horse.htm
By the way there is horse powerd machinery available from the Amish.