1. Is Tartarus true or false?
St. Peter borrows the term Tartarus to describe the prison of fallen angels. It is possibly also an oblique reference to the use of Tartarus in the Enochic literature of the 2nd Temple period, the Greek translation uses Tartarus to describe the prison of the fallen "Watchers".
This does not mean that Tartarus, of Greek mythology, is real.
2. Is Death and Hades one and the same thing ?
No. The concept of She'ol is translated into Greek as Hades. The ancient Hebrew/Jewish idea of She'ol is more-or-less just the place of the dead, and can be translated as "grave" or "pit". Hades, then, is the "place" of the dead, but it is not death itself.
3. Is Death the horseman from the book of apocalypse a person and the last enemy to be defeated ?
No, not a person. The horsemen are apocalyptic symbols, personifications of of abstract concepts. Conquest, war, disease/famine, and death respectively.
4. Is the Evil one a demon ?
The term "evil one" is usually used for Satan specifically. In the sense that we use the term "demon" to refer to all evil spirits/fallen angels/devils, then Satan would technically classify as a demon.
5. When angels take the form of a human are they 100% angel or 100% angel and 100% human or 50% angel and 50% human like a hybrid ?
They are angels regardless of how they look. Since angels aren't material, physical creatures, they don't have any "natural" appearance. So angels can appear however God wants them to appear. In the Bible the most common way angels appear is human. In the Bible angels appear in other ways too, when Moses encountered God, he heard God through an angel with the appearance of a burning bush. Ezekiel in one of his visions saw angels that looked like wheels within wheels. Isaiah when describing the angelic seraphim, describes beings with multiple pairs of wings and covered in eyes. God's holy angels look like whatever God wants them to look like based on His will and purpose. Looking human-like is probably a lot more relatable to most people than wheels within wheels, or a terrifying being of wings and eyes. It certainly probably helps in the "don't be afraid" department.
-CryptoLutheran