Whups, one last step.
Finally figured out what "Pronterface" is- downloadable here: https://github.com/kliment/Printrun#readme
It also appears to have the Slic3r included with the zip file. Anyways, after the gcode is made, you open Pronterface, load the gcode, and, assuming you have a printer plugged in, hit print. I'm betting the options are all shaded out because I don't have a printer plugged in.
Looks like it gives you all kinds of useful info- temps of nozzle and bed, estimated amount of filament used, etc..