On my PC, I do what Tim does, sort of.....

For people without Photoshop, like me...   
1. Open a blank page from Word, and once it is open, then format it to Landscape or Portrait, which ever best matches the photo. 
2. go back to the image. Find the two buttons, Alt and Print Screen , and press at same time.
3. Reopen the page and right click, the Paste option should appear so paste it, and the image of your whole screen should appear.
4. Right click again on the image, and two boxes should appear, on the upper one look for what looks like the right angle clamp as viewed from on end, if you put your cursor over it, the word Crop should appear, click on it.
5. Crop by bringing in the corners to what you want to save, and click again, this time off the cropped image, at this point the grayed areas should disappear.      
6. Click on your image again and perimeter markers should appear from which you can drag the image, opening it to the margins. 
7. And save it, of course because it is on a Word background, it will want to be saved as a word document.  File accordingly.  

Limitation is that it can't be filed as a Photo, as best as I am aware. However if it is for my personal modeling use only, no big deal.             Jim Dick - St. Paul, MN