Some of them are TinyMCE core options. You can view them in TinyMCE – Configuration.
In file /wp-includes/class-wp-editor.php there is some explanations. Obviously its not all, but it’s a start.
/**
* Parse default arguments for the editor instance.
*
* @param string $editor_id ID for the current editor instance.
* @param array $settings {
* Array of editor arguments.
*
* @type bool $wpautop Whether to use wpautop(). Default true.
* @type bool $media_buttons Whether to show the Add Media/other media buttons.
* @type string $default_editor When both TinyMCE and Quicktags are used, set which
* editor is shown on page load. Default empty.
* @type bool $drag_drop_upload Whether to enable drag & drop on the editor uploading. Default false.
* Requires the media modal.
* @type string $textarea_name Give the textarea a unique name here. Square brackets
* can be used here. Default $editor_id.
* @type int $textarea_rows Number rows in the editor textarea. Default 20.
* @type string|int $tabindex Tabindex value to use. Default empty.
* @type string $tabfocus_elements The previous and next element ID to move the focus to
* when pressing the Tab key in TinyMCE. Defualt ':prev,:next'.
* @type string $editor_css Intended for extra styles for both Visual and Text editors.
* Should include `<style>` tags, and can use "scoped". Default empty.
* @type string $editor_class Extra classes to add to the editor textarea elemen. Default empty.
* @type bool $teeny Whether to output the minimal editor config. Examples include
* Press This and the Comment editor. Default false.
* @type bool $dfw Whether to replace the default fullscreen with "Distraction Free
* Writing". DFW requires specific DOM elements and css). Default false.
* @type bool|array $tinymce Whether to load TinyMCE. Can be used to pass settings directly to
* TinyMCE using an array. Default true.
* @type bool|array $quicktags Whether to load Quicktags. Can be used to pass settings directly to
* Quicktags using an array. Default true.
* }
* @return array Parsed arguments array.
*/
You can find wpautop documentaton on Codex.