Allah is actually the arabian way of calling the monotheistic God (captial G), Arab jews and arab christians also call there monotheistic God allah. Allah is not a name, just a way of saying the "the one and only God" in arabic.
If im speaking spanish i would say El Dios, if i was speaking persian i would say khuda, in turkish, my turkish friends sometimes say TanrI, when they are refering to god (smal g), but when they are referring to God (captial G) they say allah. so when speaking turkish, i cannot say since im not a turkish, but i think its allah.
In spanish and English there are captial letters, when we are taking about the one and only God, i think we should use God capital g. but when speaking we should use God.
As for music, it is not haram, although that is one view, you pick on which is right, some of my reasons are based on this article
http://islamicsystem.blogspot.com/2012/04/q-shari-rule-on-songs-music-singing.html, and alkso this one
http://www.renaissance.com.pk/Marrefl2y5.htm, although the former more than the latter. Mostly because most of the hadiths that prohibit music are weak.
You father is right anbout the pictures, there is a hadith in islam, "In al a3mal bin anniyat", which roughly translates to, your action is justified by your intentions/will.
http://www.correctislamicfaith.com/picturesinislam.htm
read this for more clarification.
do your own research and read the links i gave you, they are useful.
I wish you luck kardesim (hope i spelt that right)
peace