try "alt + prtsc" which means "the active window" as distinct from "CTRL + PRTSC" which means dump the whole screen including the task bar and any other stuff you have in the background (which could be embarrassing or reveal your true identity).
also
If you upload max size, it makes it easier for your audience to download the graphic and draw on it in their graphic manipulation package.
For graphics manipulation (inserting arrows and text etc) I use PicPick, which is freeware, and includes screen capture and magnifiers. If you install it, turn off the bing bar installation check box if you dont want your machine to have any more microfsoft rubbish on it.
and do switch your browser to chrome or firefox if you want graphics to load faster, longer, higher, better.
