it really shouldn't be that hard, David. At the worst, you find the screenshot in your Gallery app, select the "share" option from the menu. Of the potentially dozens of things you can do with the photo from there, perhaps the simplest is to select "Email", and send it as an attachment to an email address you can access from your Windows device.
Pushbullet is another multi-platform info sharing app you might consider as a more clever solution.
I also use Google Drive as a common storage location accessible from all my devices.