I agree - it could either be a program (maybe not even a graphics program but probably is) that has added something to this context menu or it could be the dll files that Windows uses to generate and manage the context menu. (less likely).
I'd either try uninstalling anything that you suspect may have caused the problem, or use the program below to find out which centext menu item is problematic. I had this problem specifically when I right clicked and chose "properties" - you seem to have it as soon as you right click??
Download this prog
http://www.snapfiles.com/get/shellexview.html
double click on the executable file and when it runs click "type" to group the 'ContextMenu' items together. Disable these one at a time and see if any of them fix your prob.
Good luck!