Ethos, ill answer your question directly. I would like to talk about all of them. But maybe star with what JWs view as vital: The name Jehovah.
I posted this on another Christian forum, but I'll post it here as well:
Before I begin I want to say right off that I have NO problem using the name "Jehovah" and have no problem with others using the name.
As far as I have been able to see, the first use of the modern rendition of the name "Jehovah" took place in 1278 when the monk Raymundo Martini wrote his latin work where he used the spelling "Yohoua". Later printing of his work used the spelling "Jehova". As far as its appearance in the Bible, this took place in 1530 when Tyndale published the first 5 books of the Bible and included the spelling "IEHOUAH" in several verses. As far as the history of YHWH most of us know that the Masorets replaced the vowels of the name YHWH with the vowel signs taken from the Hebrew words "Adonai" (or Lord) or "Elohim" (God). So really, the name "Jehovah" is an artificial name. The Jewish Encyclopedia states that this name is a grammatical impossibility. (See here) The divine name is more correctly "Yahweh", but even this rendition is not accurate to how the name was pronounced. The true pronunciation has been lost in antiquity, due to the fact that the accurate vowels were not retained. The only reason the WT gives for using the name "Jehovah" is because it is popular in English. A friend of mine (Keith Walker) asked the question, "Well then what are JWs called in Hebrew speaking lands? Would they be Yahweh's Witnesses"? He called up Bethel and asked the question. He was told that the names of all Witnesses were based on the English pronunciation of Jehovah. He did some further research and found a Hebrew JW and learned that Hebrew JWs introduce themselves as "Yehovah's Edei". My friend asked him if they have trouble using that pronunciation with other Hebrew Jews, and the Hebrew man said that they did. He said that "Yehovah" is not the recognized usage of God's name and that other Hebrews have never heard of it. To be fair, they also don't use "Yahweh" because they do not feel that this is the accurate name of God either. He added that if people have heard the name "Yehovah", it is ONLY because they have heard of JWs and NOT because they have heard God's name. My friend concluded that this isn't consistent with what the Watchtower says in the divine name brochure. According to the brochure, people should use the name of God in their own language. But this isn't the truth in the organization. They all are forced to use the English translation of a German pronunciation (the sound of the letter "J" is from German), from the Latin rendering of a Hebrew word. In Israel, where the closest pronunciation in their own langauge would be Yahweh, they are forced to use the English translation "Yehovah". All of that being said, let's suspend disbelief and assume that the name "Jehovah" is 100% accurate. This name was how the Hebrews addressed God. It was how God told them to address Him, and they complied. It was the position of a slave addressing his master. But Jesus introduced a whole new concept. For the first time in history, those that accepted Jesus Christ were now given the privilege of addressing God as "Father". This was NOT a Jewish concept. In fact they viewed it as blasphemous. But when Jesus taught us to pray, He didn't tell us to say "Jehovah, in heaven". No, he told us to address God as "Our Father, in heaven". Why is this important? Paul expounded on this. Romans 8:15 says: "For you did not receive a spirit that makes you a slave again to fear, but you received the Spirit of sonship. And by him we cry, "Abba, Father."" The Jews were slaves. They were required to follow the Law, and in some ways were distant from God because of their position and constant need for animal sacrifice. It would be like an employee today who would have to follow all the laws of the employer and address his employer by his name or title. But we, as Christians, have a far greater privilege. We are now sons and daughters of God. The only one that has the privilege of calling someone "Father" is the child of the Father. I would never call my dad, Barry. His employees do. His friends do. But I have a far greater privilege. I get to call him, Dad or Papa, or Father. We are no longer slaves. We no longer need to address God as "Jehovah", as if we were a slave. We were received as Sons and Daughters. We call Him "Abba" or Papa or Father. Do you see the tremendous privilege here? Insisting on calling God "Jehovah" tends to deny our sonship with Him. If I was to call my dad "Larry", he would view that in some ways as a disrespect. A denying that I have the privilege of calling him "Dad". That brings us back to the place where we were slaves. It brings us back to a time when the Jews did not know God as their Father. Like I said at the beginning, I have no problem with the usage of this name. It is a mistranslation and a rendering in English that is far removed from the original. But if you prefer to use the name, that is great. But we are no longer slaves. We are children of God. And as children, we should value our EXTREME privilege of addressing our great God as "Father".