While there are powerful software such as LaTex for publishing, I would reccomend using openoffice to start with. For starters, If you decide to go back to windows, OO is there.

I'm not sure what _sort_ of publishing your wife is planning on doing, but I would reccomend writing in OO, i.e. get it to the final copy. Then once all the text is there, you could format it in LyX or similar. Although I think OO is pretty powerful under the hood.