Second question: is it permissible to give a girl the name Malaak?

Praise be to Allaah. 

It
is better not to name one’s daughter Malaak, for two reasons: 

1.                
The meaning of Malaak is
malak (angel). There
is an element of exaggeration in giving this name to a person.

2.                
It is a name which is well
known among the Christians, and it is (Arab) Christians who pronounce
the word malak as Malaak. There are many good names in which there is
no element of doubt concerning them, and those names should be used
in stead of names which are problematic or doubtful.