Try exporting the PICT file with the High Resolution option selected. You can also export the plot as a high resolution TIFF file and import that file into Word. Word for Windows (and other PC applications) cannot handle the PostScript PICT option.
KaleidaGraph is a thoughtfully designed graphing and data analysis application for research scientists, as well as for those in business and engineering fields. It produces publication-quality graphs, and easily converts the most complex data into a functional display.