I just got 9 pullets and possibly 1 cockerel 9 days ago and they were about 3-4 days old. I have 6 Buff Orpingtons, 2 Rhode Island Reds, and 2 mixed Rock (not sure what specificaly they are).
Chicks generaly like it closer to 95 degrees. You'll find out what they need by trial and error. Much like human babies, chicken babies will fuss when they need something, especialy if they are too hot or too cold. I have a 250 watt red bulb and started it out as close as I could get it (about 8 inches from them) and with a temp of 93-98, they were happy.
It does matter what bedding you use, I actualy used Carefresh bedding, it looks like soft ground up card board. Its absorbant but isnt bad for their lungs. Some people say dont use pine, but short term I'm sure it wouldn't be horrible. Some people also say the print from newspaper is bad for them, and it will get everywhere when wet. (Please correct me if I'm wrong with any of this.)
Time to move them out isn't a black and white answer. Once their wings start feathering out (which will seem like it happen overnight, literaly) they will start getting jumpy/flightly and thats when on nice days, I take mine out in the run for a few hours. At first they all cluster together in one spot, but they'll explore given time.
From what I have learned, and what I have heard from other people, its not necessarily what breed they are, but how old they are. Larger birds will of course tend to pick on the smaller ones. Ameraucanas are gorgeous and like Orpingtons get along well. I haven't had expiriance with wyandottes much, but the research I have done, they seem like a "community chicken".
Also: They love digging and such, and the bedding will get everywhere, waterbowl, floor, you name it. Plan of having to rinse water bowl out a few times a day as well as sweep around the cage.
Once mine got over a week, I went in the back and dug up some worms. They went bananas over them.
Enjoy their cute, cuddly, downy stage, they grow fast. In the past week, mine's feathers have grown in completely on their wings, tails, and started on their neck and breasts, plus they've easily doubled if not tripled in size.
Handle them frequently, but close to their space.
Like I said about them being like babies, they will peep loudly if they need something. When they're happy, they cheep lightly. You'll get to know the difference.
Lastly, sing to them. Even if you're completely tone deaf and couldn't carry a tune in a bucket, they will perk up a little and listen then start to fall asleep. Plus they get to know your voice!
Have fun and good luck!