Mormons, LDS I thought other Christian church's were "saved?"?

One must have been baptized by one who holds the Priesthood authority. The only church who has this authority is Jesus Christ's own church which is The Church of Jesus Christ of Latter Day Saints. Which is why everyone is given the opportunity to accept the saving baptisimal ordinances done for them if not given the opportunity in this life to be baptized by one who holds the Priesthood authority of God they have this opportunity to accept in the next life...thus the baptisms for those who have ped into the next life are done by proxy a/k/a baptisms for the dead. Then the answer to your question...where do mainstream Christians go? They will go to the place according to their works here on the earth. It could be one of 3 places. The Celestial Kingdom, The Terrestrial Kingdom or the Telestial Kingdom. It is all up to the person being judged at the final Judgement.