if you have your default folder or not you can edit the first one, saved as the same name as a jpg then if it worked like mine, all further screenies will be jpg..
yeah...badly explained...
open paint, after you hit print screen, ctrl v onto the paint canvas, save as jpg, and put it in the folder u want all future screens to go to...
then after you hit prt scrn while in game, if it worked right, all screenshots taken after that should go to the folder you saved the first one in, in the same format...
does that also aplies if you want to save them in png format?