Christian concept of God as in Bible (New Testament) is of a Playboy in the Penthouse of heaven who briefly visited the earth to immaculately impregnate Virgin Mary and then left his loved woman and innocent son at the mercy of the Romans.
Allah is the Muslims' preferred name for God. It signifies a being that embodies attributes of as many as 99 adjectives. The word Allah carries a sense of purity and majesty not conveyed by the more common word God. After centuries of bickering on its semantics, Muslim scholars , decided that the word Allah is a proper noun, rather than a derivative of the word elah which means sustainer, and collectively represents all the 99 attributes mentioned in the Holy Quran.