Originally Posted by
Idaho66
... they gave her a B2 visa ...
I'll try to make sure she has documentation indicating she plans to return home after the trip, not overstay, have enough money to support herself, etc. etc.
Originally Posted by
alexb133
She should be ok.. As long as she never violated any previous non-immigrant status, she won't have any problems

Originally Posted by
polonius
I had a Chilean friend who had previously lived in the USA as a student, and then subsequently returned on an immigrant visa, with the intent of settling permanently in the USA ...
I find
alexb133's advice more plausible than an 'I know somebody who had a different visa' post.
A B2 visa is a non-immigrant visa, and especially in view of the OP's precautions his wife should be fine.