Friendly as they will be around young children. Try Cochins (Pekins in UK) Silkies; any chicken will be friendly if you handle it ALOT from birth.
* They should be easy and cheap to keep. Most chickens are eaasy to keep, except for show or Onagadori!
* Easy to handle. Don't get neurotic bantams.
* Not able to fly over 3ft. Don't get bantams then, except silkies, which can't fly.
* Lay eggs everyday and are a good size. Get standard sized breeds: you could try Red, Amber, or Black Sexlinks, they lay well and have nice dispositions. Or, for beauty, Sussex, Orpington, or Wyandotte.
* hardy to cold and a generally healthy birds. Health mostly depends on management. Orpington are said to do well in cold weather. Don't get a breed with a large comb, because they can get frostbite.
* Fairly common breed/easy and cheap to obtain