There is one option in Board Config: Text Link Format. It takes the following arguments as well as plain text.
|| arguments || replacement || || $id || The image ID. || || $hash || The MD5 hash of the image. || || $tags || The image's tag list. || || $base || The base HREF as set in Config. || || $ext || The image's extension. || || $size || The image's display size. || || $filesize || The image's size in KB. || || $filename || The image's original filename. || || $title || The site title as set in Config. ||
Link to Image will default this option to '$title - $id ($ext $size $filesize)'.
To reset to the default, simply clear the current setting. Link to Image will then fill in the default value after the save.
To leave the setting blank for any reason, leave a space (' ') in it.