What issue do you have with the menu items?
I suggest you review this help topic: How skins work
Most RadControls have a base style sheet and a skin style sheet which are embedded in the Telerik assembly. However, you can view the css styles definition for RadMenu at the following location:
menu base styles
[your local installation of RadControls]\Skins -> Menu.css
[your local installation of RadControls]\Skins\Office2007\Menu.Office2007.css
the Telerik team