Table and Hr Widths:
At the bottom right of the Html Report Options window are the settings for the widths of your tables in the html report and the widths of the horizontal rule bars that separate different sections of the report. The left spinedit field is for the table width and the right spinedit is for the horizontal rule bar widths.
Below these two fields you see a pair of radio controls. The represent whether the number in the spin edit fields above them represents the number of pixels, or the percentage of the width. In other words, you can set the widths of your tables or horizontal rule bars in pixels or percentage width. If you set it in pixels, the width will always be the same regardless of whether the browser (like Internet Explorer) window size (width) changes. If you set it to a percentage, then the width will cover a percentage of the width as determined by the size of your browser.