Home Use: Pages (easy to make pretty letters etc)
Office/Dissertation Use: Microsoft Word 2008 (excellent referencing tools)
Last Resort/I have no cash: OpenOffice
Christ on a bike . . . download OpenOffice . . . MS office on the mac is terrible, simply stunningly BAD, NeoOffice was just a port of OpenOffice anyway, anything else is just asking for compatibility hassle . . . OpenOffice is the sensible choice, fast, compatible with MS, PDF, etc, and FREE . . . http://download.openoffice.org/
I've been using openoffice/Neopffice on linux/Mac/Windows for a number of years in an MS Office workplace and never had an issue . . . while you have to accept that most people fall into the FAIL that is MS software, you don't need to be one of them . . .
Fd
Well the trouble with that theory is that you also need to keep a copy of word around to make sure your documents don't look like arse when somebody else opens it (and they often do).
I would say that OpenOffice on OSX is terrible. It doesn't behave like a native app, scrolling is jerky, it crashes a lot, it's slower than the other two, the spelling and grammar checks are nowhere near as good etc etc etc. To be honest, even running Linux I used to use MS Word in WINE because OO.o is so shart.