Death and judgement day
It is my understanding from the Bible that when a person dies, his soul is separated from his body. Our bodies at this time remain on earth while a believer's soul goes to Heaven and a non-believer's soul goes to Hell. So those in death have already faced their judgement. On the day of Judgement when our Savior returns, it is my understanding that a person's body and soul are reunited and believers go to Heaven with non-believers going to Hell. Is this all correct? Also, after a person dies and before Judgement what is the status of, I guess, our souls both as believers and unbelievers? Are we kind of in "limbo"? As believers do we enjoy all the benefits in heaven with our soul (not body) or do we have to wait until Judgment Day? Same for non-believers, are they in "limbo" or are they feeling the pains of Hell before Judgment Day? Thank you.
Your understanding of events in the first paragraph is correct: when death takes place, judgment also takes place (Hebrews 9:27).
Since that is the case, Christians after death and before the Last Day enjoy the benefits of heaven with their souls, and unbelievers after death and before the Last Day experience the torments of hell according to their souls. There is no limbo of any kind. The account of the rich man and Lazarus (Luke 16:19-31) illustrates how Christians enjoy being in the presence of God and unbelievers experience suffering after death and before Judgment Day.
On the Last Day the Lord will raise the bodies of all who have died (John 5:28-29). Bodies and souls will be reunited and Christians will continue to enjoy perfect life in God’s presence according to both body and soul, while unbelievers will continue to experience suffering according to both body and soul. Those who are alive on the Last Day will not experience death but will be judged according to what is in their hearts.
Not to be overlooked is the transformation of Christians’ bodies—whether they died or will be alive on the Last Day (1 Corinthians 15:35-57). Certainly our Easter celebration is reason to praise God for our victory over death and to share that victorious message with others.