James 2:26 teaches that death is a separation of one thing from another.  Specifically death is a separation of the spirit from the body.  At death the physical body will begin to decay and return to the earth, whereas the spiritual part of our being, the soul, will continue to live.  II Corinthians 5:1 teaches that the earthly body will dissolve, but that there we also have an eternal aspect.  Genesis 3:19 teaches plainly about the physical events of death, "In the sweat of thy face shalt thou eat bread, till thou return unto the ground; for out of it wast thou taken: for dust thou art, and unto dust shalt thou return."  Whereas both the physical and spiritual are set forth in Ecclesiastes 12:7, "Then shall the dust return to the earth as it was: and the spirit shall return unto God who gave it."  It should also be said that this separation, death, is inevitable and wholly unavoidable (unless Christ returns before death comes) as is taught in Hebrews 9:27, and Ecclesiastes 3:1-8.
    As for the second question the answer is "yes" or "no."  If you are outside of Christ you have every reason to fear physical death because you will not have another opportunity to change your spiritual state once you have died.  You see any one outside of Christ is already dead spiritually, that is those outside of Christ are separated from God and ultimately will be separated from the joys of heaven.  II Thessalonians 1:9 defines this separation from God in this way, "Who shall be punished with everlasting destruction from the presence of the Lord, and from the glory of his power."  This is the death referred to in Romans 6:23, "For the wages of sin is death (spiritual-DFC); but the gift of God is eternal life through Jesus Christ our Lord."  This is also what is referred to in Revelation 20:13-15; 21:8 as the second death.
    If you are a Christian then you have no reason to fear death as long as you remain faithful.  Paul referred to death in Philippians 1:21 as a gain.  I Corinthians 15:50 refers to death as a victory.  Revelation 14:13 indicates that death is a rest from the labors of this world.  Revelation 2:10 shows that death for the faithful Christian is a time when he/she will be rewarded for faithfulness by being given a "crown of life."  I Thessalonians 4:13,14 shows the greatest thing about death for the faithful Christian:  Closeness to Christ and God, not separation, "But I would not have you to be ignorant, brethren, concerning them which are asleep, that ye sorrow not, even as others which have no hope.  For if we believe that Jesus died and rose again, even so them also which sleep in Jesus will God bring with him."