I'm glad to know that sub forum has what interests you.
Indeed God-Almighty is greater than having a son. In Quraan it says:
But they have attributed to Allah partners - the jinn, while He has created them - and have fabricated for Him sons and daughters. Exalted is He and high above what they describe.
[He is] Originator of the heavens and the earth. How could He have a son when He does not have a companion (a wife) and He created all things? And He is, of all things, Knowing.
That is Allah, your Lord; there is no deity except Him, the Creator of all things, so worship Him. And He is Disposer of all things. [6:100-102]
*Smile* at your innocence. I'm not surprised anyway, I knew this will be asked. I'll say again. Ask away! Just reword your question and be specific as killing in what sense?
To give you an idea of the basics of killing in Islaam.
1) No innocent shall be harmed, let alone killed. Be he a muslim or non muslim. Otherwise the oppressor will be punished. Either by getting killed himself (life for a life- for in Islaam, the one who kills an innocent is like he's killed the whole of humanity) or getting the same amount of harm.
It goes in a narration, the person who harms a non muslim (whose harmless to the state and muslims) is not from amongst the muslims. It's all about justice, even if the Caliph of the Muslims is found guilty of harming someone, he'll pay the price.
2) The one who harms another human is to be brought to justice, If he kills another, or stops him from practising Islaam, or is found guilty of treason or is an adulterer (if muslim), or wages a war against Muslims is to be punished by death.
[let me know if you want all these "claims" backed by poof from Quraan and sunnah and the life of those who followed Islaam]
If you want a more specific answer, than ask. Inshaa'Allaah the brothers and sisters at TTI would love to help you out.
peace.