This is my family's group computer. I'll post mine once I get to it.
Jade, the process for getting a desktop image is really not complicated... the print screen button is right next to the F12 key, and is usually labeled 'prt scr'. Hit that, and the paste the image into your image editor. If that doesn't work, you'll have to do a google search for a screen capture program, because your computer is some sort of wacko non-standard piece of junk. :)
Personally I just either use Photoshop or MS Paint for screenshots. In Paint just open the thing up, press CTRL + V, and voila. In Photoshop create a new image and the size of it should be the same as whatever has been copied.