Now there are two topics being discussed here: the name of God and the name of Jesus...
Even if God was called by some name in ancient times, like 'Yahweh' or 'Yehovah' or whatever, the fact is the jews themselves haven't called Him by that name since early biblical times. With good reason, because you kind of 'own' anything or anyone you know the name of, knowing the name gives you 'power' over someone: just think of the fairy tale of Rumpelstiltskin. However, we don't 'own' God in any way, and shouldn't think we get 'power' over Him by knowing His proper name. I think it suffices to call Him 'God,' or 'Lord,' and that's exactly what the jews have been doing for centuries.
Ofcourse, the letters of the tetragrammaton 'JHWH' are to be found in the hebrew bible, but the jews used to vowels of the word 'Adonai' to vocalize it, making it impossible to pronounce it. So now they just say 'Adonai' instead, whenever they see the letters 'JHWH' appear in the text. Facts is we don't even know HOW that word was pronounced in the first place, because the original hebrew didn't have vowels. Maybe it's just more interesting, to some people at least, to call God 'Yahweh' or 'Jehovah.' Fact is those names are just wild guesses to what the name originally must have been. Both names are also NOT in accordance with how the jews pronounce it. If you feel a strong affiliation with the jewish faith and love Israel, you should by no means call God anything else than 'Lord.'
About Jesus: could be that His original hebrew or arameic name was Yeshua, but I came to know him as 'Jezus,' and normally I see no reason to call Him anything else. Ofcourse, I call Him 'Jesus' here, but that's because most of the people here came to know Him by THAT name. Only If I talked about Him with Israelis, in Ivrit, I would probably call him 'Yeshua.' So the name we use for 'Jesus' is determined by the linguistic context; to facilitate the discussion about Him, and by nothing else.
Maybe the same that is true for calling God 'Yahweh' also applies here: it's SO much more interesting, for some people, to call Jesus 'Yeshua,' I mean, it's such a GREAT way to show off your knowledge. Interesting question: if you DO call Jesus 'Yeshua,' shouldn't you call Joshua 'Yeshua' aswell? And while you're at it, call all the people in the Bible by their proper hebrew names too?
In short: just call God 'Lord' and Jesus 'Jesus,' no need to make things more complicated than they are. And if you think the name doesn't matter, that anythings goes, then you don't take 2000 years of christian tradition and history, and at least 1000 years more of jewish tradition seriously. Hey, then there's nothing stopping us from calling God or Jesus whatever we want. But will people even know who we're referring to when we use such interesting names? There's another reason why we should call God and Jesus by their(for us) appropriate names; to make it possible for us to talk about God, to freely preach and evangelize in the name of Jesus etc, without any unnecessary confusion about their names.
