Tartan,
Sorry, I can't actually answer your question directly. But here are a few points.
Many PPL courses include a logbook in the price of your course. So don't buy anything just yet. Also, have you had a trial lesson yet? If not - and I don't mean any offense by this - but you may find that you don't actually enjoy flying as much as you thought you would, in which case it would be silly to buy anything before you need it.
It doesn't really matter what columns you have in your logbook. My logbook has an "Other" column. My insurance company want to know how much tail-wheel time I have, and there is nowhere in my logbook to record this, so I cross out the word "Other" and write "Tail-wheel" in its place.
And your wife's solution actually isn't as laughable as it sounds. Although I don't have a reference to give you, I don't believe there are any rules about where you keep the record of your hours, so long as the hours that you log are in accordance with the guidelines, and accurate.
Hope that helps.
FFF
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