Can't open settings menu in windows.

[Gospel45]

My pc has been running slow the past few days. I cant access the settings menu, I can't click the windows button, clicking cortana or the clock even does nothing. About an hour into use of my pc the whole display turns the colour of my windows. Has only seemed to happen while I'm in itunes but I have been using it alot lately. Any suggestions?

 

[Colif]

tried an anti virus scan?

what are specs of PC? Do these problems exist all the time or only after using itunes?

can you access the menu available by right clicking start?
if so, right click start button
choose command prompt (admin)
type SFC /scannow and press enter
once its run, copy/paste this line in below (Needs to be exact):
DISM /Online /Cleanup-Image /RestoreHealth

DISM fixes the files SFC uses to fix Windows, so if SFC found files it couldn't fix, re run it after DISM