From the WT own site, they admit they use the term Jehova because it is "more familiar" than they other terms, they also mention that it came from the combination of the consonants of YHWH and the vowels of "adonai".
Jehova is not the name of God, it is, at best, a popular tranliteration of 2 "names" of God from the OT.
In regards to Jesus being worshiped, I think is one were to worship Jesus OVER God, that would be quite incorrect, to worship Jesus as the son of God, to bow down before the "king of kings' and "lord of lords", to worship the Saviour, Redeemer andJudge of Us All, to do this to Jesus as the Manifestation of God, is not incorrect at all I would think.