We have had issues on a particular computer with Revit 2009 display. When we went to turn off the Open GL option in the Settings menu > option command; graphics tab, it was not available.
The graphics card supported OpenGL. If we had set NONE in the Hardware acceleration in the Windows Display properties (accessed from the Control Panel) (settings tab > advanced > troubleshoot tab), this can happen.
Autodesk also told us that the OpenGL option wont be available, if we had the 2nd monitor enabled.