Pat.
     I have " Googled" you colour problem and you can have a look at the results see if your problem is here and the solution.
If you want a cheap reliable computer shop I can recommend one it's in LAldea He is both knowledgeable and honest rare I know but I can only take as I find. He speaks English and his shop is a few doors down from the English shop that closed a few months ago. His number is 977451293. Address Av Catalunya 356 , L`Aldea 43896.

https://plus.google.com/113060074549233394170/about?gl=es&hl=en

https://www.google.es/search?q=PC%20went%20a%20funny%20pink.blue%20color%20&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a&channel=np&source=hp&gfe_rd=cr&ei=rZweVZPGNsuCbMaCgfgN

;) ;) ;)   8-)