Blue screen after logon on domain

today i must have prepare two computer to the news labor.
i installed windows vista and seven in diferent machines.After that, i put the two machines into domain and i can logon with ad, but when i logon with another user(what isn't ad) apears a blue screen with mouse. ctrl + alt + del doesn't do anithing. how can i solve this problem ?
my english isn't good, but try to help me, please.