This mignt not be exactly what you're looking for:
I've gradually come to the conclusion that its a mistake to attack a believing mate's religious beliefs in any way. The frontal assault must come from within.
Instead, try to promote a more realistic view of the world itself. Ultimately, all religious beliefs are built upon more basic beliefs, presuppositions and assumptions The JW worldview is unrealistic and facile in so many ways that the opportunities for this are endless once you start looking.
For example, my wife and I were watching the movie, "March of the Penguins" For those who haven't seen this movie, it basically covers a year in the life of emperor penguins, especially the incubation of eggs and rearing of chicks. About three-quarters of the way through the movie, my wife says, "That's just amazing" and I reply, "And they were created that way right from the beginning...."
The problem here is if the emperor penguin was originally created for an antarctic climate than the JW notion of the entire earth being semi-tropical paradise is hogwash, but if the emperor penguin was not originally created for an antarctic climate than the JW notion of every species being individually created is hogwash. Either way, part of the JW worldview is hogwash. Of course, neither conclusion will cause one to leave the JW's and that's not the point. The point is to get them comfortable with the idea of thinking, questioning and looking beyond the facile.
In no particular order, these are a few things that challenge the JW worldview in non-threatening ways: (I'm sure others could add to this list)
The Schwarzenegger movie, "The Sixth Day" graphically shows that re-creating a person and restoring their memories (JW resurrection?) is not quite the same thing as bringing the original back. (e.g. What happens if this is done while you're still alive?)
Any boat, larger than a canoe leaks. The Nina, Pinta and Santa Maria were relatively small ships (The held 20, 26 and 40 people respectively) yet they each required a bilge pump. The larger the ship, the larger the pump. Truly large ships (Noah's Ark?) have to be pumped by motors.
No member of the cat family can synthesize taurine, an essential amino acid. Taurine is not found in plants, it is only found in meat.
The interpretation of the Bible books, Daniel and Revelation has a long and colorful history going back over a thousand years. Many of these interpreters have taken an allegorical, egocentric view of these books, interpreting them in ways that would have been alien to original author or authors. (Revelation, Its Grand Climax?) These type of interpretations quickly become outdated and laughable. (The Finished Mystery?)
Some of the pyramids are older than the JW date for Noah's Flood. (Because pyramids aligned to the cardinal points, the original building date can be calculated accurately since the rate of the earth's axial precession is known.)
People are inherently unable to be rational when their religious beliefs are challenged. In line with your reading recommendations, the hatemail that Mormon "Apostates" like Jerald and Sandra Tanner have recieved is a non-threatening way to get this point across. (JW's believe that people are capable of being rational and in fact, God judges them on this basis. That's the whole premise behind parallels between themselves and "The Watchman")