Occasionialy, the tool bar will dissipear, and all images will not be displayed on any webpage, as well as my tab bar loosing all shading and becomeing stark gray with no icons on the tab bar, what's going on?

Every once in a while, the top bar, the refresh, cancel, back forward icons, as well as the icons in the favorites tool bar will vanish completely, and the tabs will loose all icons as well as any color and shading, and the x at the end of each tab. I'm including a picture of what I mean. On occasion, the problem will fix itself, only to return later. This is the image: http://tinypic.com/r/1pz6gk/7 Thank you very much.