I will throw my two cents in, which is rare for me. Admittedly I am biased since I raise and breed Rhode Island Reds, but don't rule them out because of reports of aggression. The birds you buy at a feed store or from a hatchery do have that reputation, but in both appearance and demeanor they are totally unlike a true standard bred RIR. My birds are very, very docile, to the point that I have to be careful not to step on them when I'm in their pen. I don't handle my birds much at all, but they will let me reach down and pick them up if I choose. I also have bantam RIR's and they are amazingly friendly little creatures that lay a big egg for a bantam. I have also raised Standard bred Barred Rocks and while they aren't quite as friendly as the reds, they are still very easy to work with. I guess what I'm saying is don't consider chicks you buy at the feed store or hatchery to be the same as what a breeder will come up with. If you are just concerned with maximum production, by all means go the hatchery route.
Thanks for your replies! I will look into turken, I haven't looked at those yet. Jersey giants, I believe are pretty slow maturing? I ruled them out due to that after reading some other threads about best dual purpose birds... Barred rocks, wyandottes, and orpingtons seem to have quite a following on some threads on BYC as dual purpose birds that are good winter layers, which is why I started with them.

I agree my barred rock is my best layer, and pretty big--I really don't like her temperament, though, and I have a small daughter (3 y.o.) that I hope will help me with the chickens as she gets older, so I need kid-friendly, or at least not aggressive. What are others' Barred Rocks like? Do I just have Ms. Crazy Bird, or are flighty peckers common?
I ruled out RIR due to reports of aggression, though I have no personal experience with them. I have actually read tons about different breeds and studied the Henderson's breed chart and whatnot. I guess I was more wondering what local people were having success with, as since BYC is such a wide community, sometimes breeds that are working well for people in other climates aren't suitable for ours. And also a lot of people on BYC are pretty dismissive of hatchery quality birds, complaining that they have had most of the "utility" bred out of them; I've seen the same complaint about people focusing on show quality plumage at the expense of egg production/forage-ability/body type/etc. None of this is from personal experience, just what I've read (and I think show quality birds are beautiful!), so I'm not trying to offend anyone here. I'm really just wondering if hatchery birds are poor stock, and show birds aren't the best utility birds, then where does one find good utility birds? Are some show quality birds also good utility birds? Do local breeders exist for utility-type birds? Are there breeders around that are focusing on good dual purpose birds, that sell chicks/hatching eggs/etc? If so, how do I find one? I guess this was my attempt at finding one!
I'm also a sucker for pretty birds--I love the GL Wyandotte coloration, and the BBS english orpingtons. The cream leg bars were a whim (the orpington breeder also had CLBs, and offered a free cockerel, so I picked one and a hen up as well when I got my orpington chicks), more for eggs and pretty birds than dual purpose, and I may or may not keep them. I thought I was getting good English Orpington stock, which I was going to use to start moving more towards dual-purpose than layer; the breeder advertised good lines (that I knew about from following the English Orpington thread here), but then has not responded to any inquiries made by me since I purchased the chicks--so I'm guessing I got suckered into buying poor stock from a breeder just out to make a buck. That was my first experience buying from a breeder rather than a hatchery and it was a pretty poor purchase experience. I'm hoping fellow BYC'ers can point me in a better direction for local breeders rather than relying on classifieds.
I'm also trying to keep a fairly sustainable flock going, so I don't want to just raise broilers. Although I don't know if a flock as small as mine can truly be sustainable--probably not, without outside stock, as I mentioned earlier. Space and neighbors aren't issues, we're pretty rural with over an acre, but I don't really want to produce many more eggs than our family eats. And a handful of chickens can free-range our yard without mass destruction; more would probably impact the garden. Two of my hens went broody this past summer, and next year, I'd like to let any broody's raise chicks to replace the layers and fill the freezer.
Oh, boy, I can be long-winded when I get going...

sigh...