Personally I'm just using ALT+PrtScn which will print-screen the window, from there, just hop over to your favorite image editor (Paint, Photoshop, GIMP, ETC.) and paste it in (CTRL+V) and then save it to your desktop in a JPEG format (low resolution so that the forum doesn't throw a fit when you try to upload it as I've found.
Another option is to use PUUSH or a similar advanced screenshot tool, but that's an extra download, which may not be your cup of tea, but will save it to an online repository in a consumable format without needing to go through the image editing portion of the first suggestion.
