Welll , dirty and simple way would be to take a screenshoot of the render , open it in MSpaint or gimp(a few meg ,allow you to change compression rate, right clik on the picture , then clik save ) , then save it as jpeg .
Better way would be to use the add plugin buton in the menu , then you browse to the dir where you installed wings3D and add the yafray export plugin ,then render using yafray,save it open the render with gimp , and resave it as jpeg.
( for installing yafray plugin, look in the man of wings3d, but basicaly you need to add the yafary directry to your path)
Other way would be to export as .3ds , then render it into you favorite app.
I am gonna add wings 3d , the exporter and povray to the download section
