Graphviz and dot
I’ve been puzzled a bit by the graphing output of gramps – it leaves me with a file with a .dot extension that I didn’t know quite what to do with. It opened in text editors as just markup, no image viewers I used seemed to like it, so I researched graphviz (as that is what is used to make the dot file…) and found that there are ways to get an image out of a dot file… (the easiest is a command-line $dot -Tsvg strangedotfile.dot>strangedotfile.svg ) which should give you a scalable vector image with the same information as the .dot output (of course you can use -Tpng to specify png as well.) (BTW, the default settings with gramps give you a single page maximum so things may be VERY scrunched to fit in.)
If you don’t know, gramps is a very good open-source genealogy database application for unix platforms. (I think there may be a windows version as well.)