As for the replace command, you may exclude files from the list by unselecting the respective checkbox in the file list. Files thus excluded will not be be taken into consideration.
This tab allows you to extract matches from a set of files. After you hit the "Extract" button, a sub window will pop up that displays the result of the operation. You can now decide to store the result in some file on your system for further processing, or just examine it. The following options allow you to steer the result.
If you choose to extract whole lines, not only the match of the specified expression will be displayed, but the entire line (or lines) where it appeared. Choosing this option further allows you to let FAR print line numbers and even to print additional context. This means you can specify a number of leading and trailing lines that should be be printed before and after the match.
By default FAR prints the file name of each file examined as well as the actual matches. You may decide to omit either, but not both (either file name or matches must be printed). Omitting the actual matches can make sense if you are only interested in printing the match count.
Eventually you can specify the separator used to delimit the matches. FAR proposes you a blank line, no separator (that is, a single line break), and three hyphens (---). The latter separator can be customised. Type into the text field of the drop down box to define a separator of you choice.