public static void UserConfigLoad() {
    try{
      Properties p = new Properties();
      p.load(new FileInputStream("user.ini"));
	myUsername = p.getProperty("Username");
	myPassword = p.getProperty("Password");
	fixed = p.getProperty("FixedScreen");
      }
    catch (Exception e) {
      System.out.println(e);
      }
    }

  public void UserConfigSave() {
    try{
      Properties p = new Properties();
      p.load(new FileInputStream("user.ini"));
      p.put("Username",""+ myUsername +"");
      p.put("Password",""+ myPassword +"");
	  p.put("FixedScreen",""+ fixed +"");
      FileOutputStream out = new FileOutputStream("user.ini");
      p.save(out, "/* Server Info Updated */");
      }
    catch (Exception e) {
      System.out.println(e);
      }
    }

Fixedscreen is a boolean so its either true or false.
Username is a string.