the equipment should be unobtrusive, a dictaphone is ideal, whatyou mustn't do is ask her specific questions, I did an interview with my dad in 1998, i just asked him to talk about his childhood, i used a casette of course, i have almost 180 minutes of him talking and it ia pricel;ess, but it's the info you get to read between the lines, it a amazing, always make sure the person is relaxed, and subty prompt them, don;t talk in dates and facts, let them tell their own story. transcribe it word for word in hard copy, it is amazing what you miss otherwise, that takes alot of time but it worth it. transfer it it CD and you have an amazing momento. i can't pluck up the courage to listen to my dad's voice now that he is gon, but one day i will.