We use this prayer too, it's one of the oldest recorded prayers,
Priest: O God of spirits and of all flesh, You have trampled upon death and have abolished the power of the devil, giving life to Your world. Give rest to the soul of Your departed servant (Name) in a place of light, in a place of repose, in a place of refreshment, where there is no pain, sorrow, and suffering. As a good and loving God, forgive every sin he (she) has committed in thought, word or deed, for there is no one who lives and does not sin. You alone are without sin. Your righteousness is an everlasting righteousness, and Your word is truth.
Priest:For You are the resurrection, the life, and the repose of Your departed servant (Name), Christ our God, and to You we give glory, with Your eternal Father and Your allholy, good and life‑giving Spirit, now and forever and to the ages of ages. Amen.
People:Glory to the Father and the Son and the Holy Spirit, now and forever and to the ages of ages. Amen
Source:http://www.goarch.org/chapel/liturgical_texts/memorialservice
We are not permitted to be cremated as well.