Screenshot size issue in MBPR-Windows

Im using bootcamp to play LOL on Windows 7 with my Macbook Pro Retina 15'

I want to take screenshots to help a friend of mine learn the game.

I discovered that if you take screenshots on Windows with MBPR 15', the screenshot saver only captures a portion of the whole screen.

I suspect that this has something to do with Retina display having too high resolutions / windows not being able to fully support it.

I am wondering whether there is a way to solve this issue (adjusting settings, using a 3rd party program etc.. doesnt matter much to me)

[im also uploading a screenshot taken for example../ Nvm it seems that the screen pic won't upload due to file size, again thanks to great resolutions ]