Compile question..

Hello,
      I want to change the buttons on my main menu bar.I know I have to edit the buttons in the langs/lang_english.php.I have tryed that and It dose not work,So I asked about it and found you have to compile after the switch.Well with me being a newbie,I have no idea what recompile is.So how do I recompile the file after I enter my button information?Any help here would be great..Thanks in advance...Disstudem