First so we don't have to turn our computers 90˚ to read your graphic learn to make screenshots:
How to take a screenshot on your Mac
(⌘⬆︎3) Command-Shift-3 Capture the screen to a file
(⌘⬆︎⌃3) Command-Shift-Control-3 Capture the screen to the Clipboard
(⌘⬆︎4) Command-Shift-4 Capture a selection to a file
(⌘⬆︎⌃4) Command-Shift-Control-4 Capture a selection to the Clipboard
(⌘⬆︎5) Command-Shift-5 Invoke new screen grabber
Paste the following command in the Terminal window followed by the Return or Enter key to change the type of screenshot file to jpeg:
defaults write com.apple.screencapture type jpg && killall SystemUIServer
Past the following commands in the Terminal window followed by the Return key to change the save location of screenshots to the desktop.
defaults write com.apple.screencapture location ~/Desktop/
killall SystemUIServer
Boot into Safe Mode according to Start up your Mac in safe mode - Apple Support and see if the problem persists. Reboot normally and check again.
NOTE: Safe Mode boot can take up to 10 minutes as it's doing the following;
• Verifies your startup disk and attempts to repair directory issues, if needed
• Loads only required kernel extensions (prevents 3rd party kernel/extensions from loading)
• Prevents Startup Items and Login Items from opening automatically
• Disables user-installed fonts
• Deletes font caches, kernel cache, and other system cache files