Simple Inquiry: Editing all Tracks Simultaneously.

You can press ctrl+A to select all tracks, then drag select the region you want to remove in the timeline. Then use Edit--->Delete..... from the menu and make sure "Delete  Hole" is checked along with the "Events in track" option and any other items you want to delete.

Then click on okay.

Of course Karl is right.

Another way to achieve the same thing but in non distructive way for future reference is, control + A to select all tracks then use the mouse on the edge left or right edge depending on the way you are trying to edit then drag the clip in the direction you want to remove the audio (slip editing).  As you ave selected all tracks this will slip edit all tracks at the same time. To undo, select all tracks again and drag in the opposite direction. 

Just an alternative to the great advice from Karl.

As StinGa has pointed out there's usually several ways of achieving the same thing. ANother way would be to select all tracks and split the clips where you want them to start, then delete the parts you don't want.

That's very similar to StinGa's suggestion. My first method will remove all of the time as well which may not be what you want.