Hope someone can help me on this one because it is driving me crazy!

Some of my documents and pictures in my vista folders look grayed out or muted. They open fine. What would cause this to happen? I have tried everything I can think of to fix it. When I open my pictures folder the colors on the thumbnails are muted but when I double click they open in preview in full color? I also ended up with a shortcuts to these folders which may or may not be the same issue. Anyone??....