tinyMCE editor is more stable than the FCK. It is best when you can use most of tinyMCE options.
To add all the options use the below "TINYMCEOPTS" located in the "config.php" file (after enabling tinyMCE).
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define "TINYMCEOPTS", ",plugins : 'devkit,style,layer,table,save,advhr,advimage,advlink,emotions,iespell,insertdatetime,preview,media,searchreplace,print,contextmenu,paste,directionality,fullscreen,noneditable,visualchars,nonbreaking,xhtmlxtras', theme_advanced_buttons1_add_before : 'save,separator',
theme_advanced_buttons1_add : 'fontselect,fontsizeselect',
theme_advanced_buttons2_add : 'separator,insertdate,inserttime,preview,zoom,separator,forecolor,backcolor',
theme_advanced_buttons2_add_before: 'cut,copy,paste,separator,search,replace,separator',
theme_advanced_buttons3_add_before : 'tablecontrols,separator',
theme_advanced_buttons3_add : 'emotions,iespell,flash,advhr,separator,print,separator,ltr,rtl,separator,fullscreen',
theme_advanced_toolbar_location : 'top',
theme_advanced_toolbar_align : 'left',
theme_advanced_path_location : 'bottom',
plugin_insertdate_dateFormat : '%m-%d-%Y',
plugin_insertdate_timeFormat : '%H:%M:%S',
extended_valid_elements : 'a[name|href|target|title|onclick],img[class|src|border=0|alt|title|hspace|vspace|width|height|align|onmouseover|onmouseout|name],hr[class|width|size|noshade],font[face|size|color|style],span[class|align|style]'
");