What has your religion ever been right about?
Why did you become a JW and take it from there.
You need to give them something to think about later but we all know the constant stream of information from the WT keeps them from really ever thinking about anything but that.
Really thought there's probably not much you can say unless you happen to say it at the right time. Even JWs admit that most of the preaching work is coincidence based. Go to the same houses over and over and over knowing that eventually some tragedy is going to make some people receptive. I know some people that would find people to write to by reading the obituaries.