Disable everything like Alert.show() - Please help!

Trying to look through all the classes to find out how the Alert.show() using the Modal window causes EVERYTHING to disable. I’m creating an application and there times where I have a popup window that is completely custom but I need everything to disable like the Alert.show does.

The reason I didn’t know if there was an easy ways is there are HUNDREDS of instances of things to disable (unless you can disable an entire movieclip with buttons, etc in that movieclip).