Even if everyone had the same general understanding of God, which perhaps they do to some extent, we would not be able to translate the whole being into understandable language, or language at all for that matter. However, I think we can offer glimpses of God and convey our partial understandings limited by human potential.
I'm not a theologian or a guru, but here is my effort to convey what I understand about God, though there is no way I could do Justice with it.
First, God is omniscient, omnipotent, and omnipresent. He exists outside of time and space, but is active in the universe, especially with humans.
God created the universe, in one way or another, with or without the big bang, with or without evolution. I happen to believe in both.
Because He exists outside of time and space, he has knowledge of the past, present, and future, even before it passes--here you see the futility of trying to explain Him.
God is also loving and benevolent. He is the true good.
At some point after the creation of the universe, human beings came into existence, which God purposefully created in His image and likeness. This does not mean God has arms and legs, as God is outside of space, but by looking at ourselves, we can achieve a glimpse of the identity of God. God is the Being who gave humans souls, which mimic God, and seek completeness by being in union with Him.
God plays an active role in the lives of people through various means because He created us for a purpose and wants us to choose to pursue union with Him.
This is a basic idea of the God of at least Christianity, Judaism, and Islam, and perhaps other religions I am not aware of.
My understanding of God goes further than this and more in depth in regards to His relation with people, but all this is more specific to my religion, and may diverge from others' perception of Him. If you are interested I'd be happy to share more details.