How do I change my screen size back to normal?

The computer was acting slow again. This is the second time it's acting slow for the whole day, so I restarted my computer. Now everything in my computer went big. I try restarting it again, shutting it off then turning it back on, but those 2 did not work. I try changing the resolution, but it isn't proportional as before and it's blurry. I ALSO TRIED SYSTEM RESTORE, BUT IT'S THE SCREEN SIZE DID NOT CHANGE! AND I SET IT BEFORE THE PROBLEM OCCURED.



What I mean by screen size is the icons, letters, microsoft word letters, internet explorer images, etc... Please help, thank you.How do I change my screen size back to normal?
go to were you changed the resolution and move the indicator one step to the right.How do I change my screen size back to normal?
right click on desktop. view. view small icons.