With the game window up and active press the Alt + Print Screen button on your keyboard, this will take a screen capture of the active window (our game window in this case) and copy it to clipboard.
Next up open MS Paint, (Start > Programs > Accessories > Paint) or any graphic package, after creating a new document via File > New or similar go to the Edit > Paste menu and it will paste your clipboard into the picture.
Save the picture to your Hard Disk, in a folder you can remember. On the File > Save screen select your file type as GIF or JPG format these will create a much smaller image perfect for email or web posting purposes.
If someone has asked you to send them a screenshot, open up your email program of choice then attach the picture you made to the email and send it to the email address you were given.
Typically if you are trying to email the GM the email address will be mailto:support@landsofhope.com