How to create a EMAIL PAGE button

I actually have a similar question to Richy 55’s printing btn question.

I’m wanting the viewer to be able to press an email button, when this is clicked I want to take a snap shot of whats on the screen at that time and send it out.
So basically I just want to know how to create a “email this page” button.
If there is any way to screen capture a certain size of what you see and send out only that part, please let me know as well.
Thanks,