holly...Regarding the blood issue, if you have not read Ray Franz' In Search of Christian Freedom, I would recommend you to read his chapter on blood on the following website:
http://www.commentarypress.com/eng-search-ch9-01.html
It is one of the best written essays I have read on the subject, and shows very clearly how the Watchtower interpretation "goes beyond what has been written" and follows the example set by the Pharisee rabbis of treating "man's rules" as the equivalent of "God's law". I also might suggest that you read Paul's detailed discussion of "food sacrificed to idols" in 1 Corinthians, especially whether he shows any awareness of a commandment against consuming meat sacrificed to idols (which, not having been bled according to the Jewish manner, would have also contained blood). The answer may surprise you.
On the subject of the Trinity, it is important to distinguish between the issue of Jesus' Deity and the issue of whether God is a Trinity. The latter represents a theological construct seeking to harmonize various differing statements in scripture, the former is one of the concepts in the NT (and elsewhere in early Christianity) that was harmonized into the Trinity doctrine. The NT embraces different christological conceptions, but a number of these do presume the Deity of Christ (cf. John 1:1, 20:28; Colossians 1:19, 2:9: "For God was pleased to have all his fullness dwell in him...For in Christ all the fullness of Deity lives in bodily form"). Most striking is the practice in the NT of applying to Jesus Christ OT scriptures referring originally to Yahweh. Note especially how Revelation 1:8, 17-18, 2:8, 4:8, 11:17, 21:6, 22:12-16, etc. apply Isaiah 44:6; 45:11-13, 51:13, 15-16, originally referring to Yahweh, to both Jesus Christ and the Lord God Almighty, or how Isaiah 45:23-24 is applied to Jesus in Romans 14:11, Philippians 2:10-11, or most strikingly how Romans 10:9-13 applies Joel 3:5 (referring to the "name of Yahweh") to Christ. The New World Translation, in many of these instances, inserts "Jehovah" into the text of the NT to obscure the fact that Jesus is being identified with the Lord God of the OT.
If the Son is described as having "the fullness of God" or the "fullness of Deity", and if he is described as "the perfect copy of [God]'s essence" (Hebrews 1:3), or simply as "God" (John 1:1, 20:28), and if the NT regularly applied OT verses describing the Almighty God to Jesus, then there is probably more to the teaching than the Watchtower is willing to admit. There is no sort of developed doctrine in the NT of how both the Son and the Father could be God and how the Holy Spirit fits into the overall picture, only early Christians who had no problem with confessing Jesus as Lord and as God. Working out the precise theological details was left to later church fathers, who developed the Trinity as a plausible rationalization and harmonization of different christological concepts in scripture. One interesting idea from the second-century apologists (who lie roughly mid-way between the primitive NT conceptions and the Nicene Trinity) is that the Son was God because he was begotten by the Father, and thus had the same divine nature as the Father (as Colossians and Hebrews imply), and was not separated from the Father as if he were a second God but rather both were united as one God -- but at the same time internally distinct as Father and Son. This harmonizes statements in the NT about the Father and the Son being united and about them being distinct from each other and even different in role (with the Son being subordinate to the Father). The Watchtower commonly cites scriptures emphasizing a distinction between the Father and Son as proof against the Trinity, but this involves a misunderstanding of what the Trinity claims (i.e. it does not claim that the Father is the Son).
The Watchtower's beliefs about the resurrection, the soul, and hell also do not correspond to actual Jewish and Christian first-century beliefs as attested in the NT and other writings. For instance, compare 2 Corinthians 5:1-10, 12:2; Philippians 1:21-24; 2 Peter 1:13-14 with the Watchtower teaching that nothing like a soul leaves the body at death, or Paul's discussion of the resurrection in 1 Corinthians 15 which assumes continuity of the individual between life, death, and resurrection (unlike the Watchtower teaching of the resurrection, which denies such continuity).
The most fundamental doctrines of the Witnesses are those that even more clearly cannot be shown to be based in the Bible. Where in the Bible does it say that God chose the Watchtower and Bible and Tract Society in 1919 to be his "organization"? Where in the Bible does it say that the New Covenant effectively closed in 1935 except for "rare exceptions" and is no longer offered to new Christians? Where in the Bible is the group numered as 144,000 declared to be the only group to have a heavenly destiny and corresponds to the number of those under the New Covenant? Where in the Bible is it declared that Christians belong to two distinct "classes" and that Jesus is the mediator for only one of these classes and that the other must depend on the other for salvation?
These are some questions worth investigating if you feel that the Witnesses only believe what's in the Bible. Bear in mind too that there are other Christian groups who do not believe in the Trinity or hell and so forth, but the teachings I highlighted in the last paragraph are definitely those peculiar to JWs. These are also the most critical teachings, because they are teachings that would make you dependent on the "organization" rather than Christ for salvation, and give the "organization" the authority to control almost every aspect of your life.
