The min width is intended for use on small screens, such as PDAs.
The thin width is also rather minimal, but includes the search info at the top so you can easily do a new search.
The wide width is the default. It includes a brief explanation of the columns. It also has a line counter and sometimes links to footnotes at the left. And it has the Hdrs column, showning which ABC headers are used in the tune. (A double quote " is used to show that a tune contains chords.)
The max width shows everything known about a matching title, and even has borders on the table fields.