Close all open windows in the Finder. Open only one new window. Without clicking on any of its contents, set it to the view you would like (and if it is column view, the width of the columns you would like - hold option down as you drag the size bars to resize each of them equally) and adjust the sidebar width to be what you want. Then close the window.
From now on, all new windows should open in the same format. Exceptions to this are the first window that is opened after a restart which defaults back to the original column widths (a bug that is still not fixed after 7 years of OS X, sigh), any windows for which you have set the views independently, and any disk image windows which will mount in the view set by the software distributor.
If it doesn't work, then you must have clicked the window content area.