Re: is calligraphy allowed in islam?
I don’t see why not but I find it a bit disrespectful when they make animate objects out of it like making peacock shapes with curly writing when writing the name of Allaah :swt: or a lion when writing the name of 'Ali 
(he is indeed the Lion of God, but no need to break laws).
Quranic calligraphy is a beautiful part of our culture but if you’re going to put it up then respect it, don’t take drugs (smoke etc.), swear/curse or watch/listen to unIslamic things on the TV if it’s in the room. Also don’t just hang it there, make it practicle and use it as a reminder to read the Verses and Prayers so Allaah will bless your home.
I wouldn’t think mere hanging up verses on it’s own will have much blessing though so use them for reading off.
It’s no religious requirement to hang them up though, I personally like the idea that there is no iconography in Islaam, we don’t have any symbols for worship like the Christians have the Cross, the Hindus have all them statues/idols, us Muslims don’t have any such thing (the Crescent-Star has nothing to do with Islam), we are devoted to and worship the True Lord who is so Great that He is beyond our imagination/comprehension so icons/symbols are useless. It remninds me of something I once heard “the non-Muslims wear their coat with the fur on the outside but us Muslims wear it on the inside” (our religion gives inner satisfaction/serentiy/peace whereas other religions resort to superficial rituals and show.