It is great that you are researching so early! That will be so helpful for you : ) There's lots of great information on here about all your questions . . . here's some basics, but you can do a search on each question that will turn up lots of information! Everyone has a slightly different way of doing things too - I enjoy finding out about different approaches.
First of all, I ordered 8 American Buff Goslings from Metzers. I then found an adult pair of grey geese (probably Toulouse) locally. I fed the goslings free choice non medicated (important!) chick crumble as much as they could eat. I also was lucky enough to live on an organic farm with lots of grass so I'd give the babies a chunk of sod (scraped from our ever present concrete cracks) every day or so. They LOVED that, and it was funny to see them wrench at the grass with their little baby feet braced : ) I never measured food, but any basic goose book probably has exact measurements. I didn't have the adult pair until the buffs were mostly feathered out.
Now as adults they love layer pellets once a day but will turn those down for better food - such as grass, apples, snacks from you, dandilions, watermelon . . . I don't measure their food - I can tell when they are done when there is food still left on the ground. Mainly my grown geese are rotated onto new areas of grass every week or so and they eat on that with great enthusiasm.
My Buffs were raised with ducklings, and they will flock with the ducklings. The pair of adult Toulouse came when the ducklings were mostly grown, and they don't care one way or another about the ducks. As adults, both ducks and geese have little spats,) but they seem to coexist fine as long as they have enough space. Usually the ducks will travel around in a little flock and the geese will be with each other too, so space would definately help if you were going to have them together. The drakes have even chased a couple of the geese, but that is happening less as the geese mature.
I would go with 4 instead of 8 to start with -- with 8 it is harder to give them all attention, they require larger grassy areas to feed on, and they make a mess more quickly. I love my geese, but I know I will want to keep some goslings next year, and since I already have 9 geese, it is going to be hard to keep very many before I have to buy more fencing . . . plus, i have yet to encounter breeding geese, and if all of them pair up that will make for a lot of nests / shelters / special goose areas next year . . . not to mention dealing with whatever behavior changes there are . . .
I think top Show Quality only matters if you think you might want to show them , or if you have a local market for top quality birds that will also pay top quality prices. The coloring will be better/more regular on the Show Quality birds too. If you can spend the money though, and you want show quality, I don't think there is anything wrong with getting them for no reason but that they are what you want. I think breed choice is really a personal thing - everyone has a favorite breed or bird, and you should go with what interests you. I chose Buff American because they were one of the reportedly friendliest birds, I considered Pilgrim Geese for the same reason. Now I think I would get the Pilgrim because you can tell so quickly whether you have males or females - one of my goslings didn't make it and now I have an odd number . . . I'm pretty sure it was a female that died, but I guess I'll find out next spring. I don't have the time to get into showing, and I don't think there is much local interest in fancy geese so the Buff seemed like a nice compromise .
Good luck on your goose research!
