It really depends on the hen, I have had some leghorns that will never go broody and then some that wont stop going broody, really every breed I have ever owned has been like that.
Eastereggers usually have green legs, ameraucanas usually have slate blue legs. I stole this from a nother post on here.
Ameraucana:Ameraucana Breeders Club for info and pictures
Ameraucanas are not that common and should be purchased from Breeders
Breed info:meets APA's Standard of...
Eastereggers and ameraucanas lay blue eggs, Eastereggers are what hatcheries sell as Ameraucanas but they really arent.
Here is a picture of a common color in eastereggers.