It sounds to me like you're losing your wife to them. Don't try to focus on too many things at once because it gets confusing and it gets nowhere. Doctrinal points are very hard to point out, especially to JW's because they're under heavy mind control and it doesn't matter what the Bible says, it's what the Watchtower says that's important to them.
My suggestion for your wife is this: You need to focus on the organization, it's policies (shunning), it's history of flip-flops (superior authorities) and false prophecies. You can start with the Generation teaching that went on for several decades, and then move backwards to 1975. You can also go over 1919 with her, and explain to her that back then they were still teaching that Russell was the FDS (until 1927), that in 1919 Rutherford stated the WT no longer needed the Holy Spirit and instead received "messages" from angelic creatures. These are key points because if you can convince her that Jesus would have NEVER picked them as the only true channel, then Jesus STILL has had nothing to do with them.
OR you can do this: Galatians 1:8. If you can show her using the Watchtower's literature that they are preaching a "different gospel", and they HAVE admitted this, then you also have a chance of proving to her that this organization is false.
Just my suggestions...