Marion, PageMaker has been a dead product for many years now. It is certainly not supported on any if the newer OSs, and it's almost a miracle that you can use it at all under Vista.
Time to move to InDesign, or to get an old machine running Windows 98 for working in PageMaker if you don't want to make the move.
The way to install missing dictionaries is to insert the PM Installation and do a custom install, selecting only the dictionaries you need.
However, PM6.5 is positvely archaic, obsolete and not designed to work with WinXP or later.
Best of luck!
Iechyd da! John
19:05 17/01/2010 GMT