My roommate gave our landlord 30 day notice verbally but she did it because we were in a fight and her new apartment is not ready in time. She has nowhere to go now so, can she take it back since a written notice was not given?

Depends on the landlord. If they have already started advertising for a new tenant, they might hold her to it.

A verbal notice is as legal as s written one, and she is still wanting to move right, but her new place just not ready yet? The landlord may allow them to so they need to go and talk to them.