Windows XP's defaults for console application windows (ie: the windows in which filePro runs) do not work well for filePro. For example, if you press Alt+Enter to switch to full-screen mode, filePro will occupy only the top half of the screen.
To change this, right-click on the icon you use to start filePro and select "Properties". Then click on the "Layout" tab. From there, change the "screen buffer size" and "window size" to a width of "80" and a height of "25". If you plan on running in a window, rather than full-screen, you should then click on the "Font" tab and select the font size that you prefer.
Note: when setting the font size, you should make sure that "Raster Ronts" is selected, as Windows will draw the screen faster and more efficiently than selecting "Lucida Console" or some other TrueType font.