Wow this sounds very interesting but i want to add some things in this post which i think you should mark.
Microsoft had posted a component named DSO Framer in which they have given handle for hiding file menu's as well as office button also. That control is able to hide any office version main menu and even office button (application menu) in office 2007/2010.
But due to some reasons they have removed the component from their post and also they r not providing any support to do same task.
This Excel viewer is just amazing but atleast you should add some handles in your component so user can easily hide or deactivate anything they want on office window.