How to disable the mouse right click?

By default, HTML Executable replaces the default context menu in Internet Explorer (shown when you right click on a page) publications by its own menu. This ensures that no "Show source code" menu command is available.
If you really want no context menu at all and for all HTML pages, you need to edit the Default security profile:
(go to the Security tab, select Security Profiles, etc...) and add the "disable right click" option.