If your talking about the button itself:
It should automatically default to left click, and windows key opening the start menu..
(but you can change that on the controls tab, by checking "Show all settings")
Are you trying to remove the users ability to right click on the button? Im not sure if this is possible
If your talking about the menu:
in what specific ways doesn't the 'windows 7 style' not act like the windows 7 start menu?
I believe you may be correct in me not understanding

, and a specific example or 2 might be helpful.