JOEL - In the scriptures you mentioned, Jehovah was trying to persuade the Israelites from worshipping the many false gods of their neighbors, and he wanted them to focus on their God, Jehovah, who is Jesus Christ. Even though the LDS believe in the existence of other gods, they do not worship them since those other Gods have no authority over them. In 1 Cor. 8:5,6 it says: "For though there be that are called gods, whether in heaven or in earth, (as there be gods many, and lords many,). But to us there is but one God, the Father, of whom are all things, and we in him; and one Lord Jesus Christ, by whom are all things, and we by him."
Paul is saying that even though there are many gods and lords, we worship only God the Father. We worship Him alone since He is the Father of our spirits (Heb. 12:9). We all have parents and are subject to them only and not to our grand parents or great grand parents or anyone else's parents. The same idea applies to God.
Also, He is not just the God of this earth but of the whole universe and this existance as we know it. The other gods we talk about are the Gods of other universes in other times, past and future. This is hard to comprehend, but the prophets seemed to understand it well, including our latter-day prophets today.
Actually, in the Church we don't really spend much time talking about concepts like this. We tend to focus more on what we need to know and do right now in this life.