Why has my computer display changed colors?

Please help! Changed display pic now computer is slow :((?

• Hi ! I dont know alot about computers, but I right clicked on a photo and put "make display background" when it did, I noticed an immedaiate slow down in my computer :(( i figured out how to right click on the screen and change it to "blank". but my computer is still slow ! What can I do?? Help please and give me step by step ; i dont know how to do computers; Thanks

• Answer:

  Select Start Menu, Click on Run and Type "%Temp%" and And temp folder opens and Shift-Delete all the data in that folder, all that data is just junk. and Go to google Search for CCleaner and Download ,Install and Run, it will delete all the waste in your computer which slows it down and Clean Registry also.(There will be a option for that) Another, Right-Click on Desktop and Properties, Go to screensaver and select none in the list. and If your computer is still slow, Use Disk Defrag - Start - Accessories-System Tools-Disk Defragmentor, Even not slow.. Use it for Quick Access of the data on your hard disk and fast reading times, Arrangement of your data in order. Still slow? Change your theme to windows classic and disable thumbnail previews in My computer. Press f10 if your using vista or 7 or Go to toolbar, press tools go to folder options in that view -- advanced settings tick- Always show icons, never thumbnails. - Check with this option first if you are using vista or 7, Cause this could be the main reason for many.