Форматирование носителя

Используйте ShFormatDrive:

function SHFormatDrive(hWnd: HWND; Drive: Word; fmtID: Word;
     Options: Word): Longint; stdcall; external 'Shell32.dll' name 'SHFormatDrive';

const
  SHFMT_DRV_A = 0;
  SHFMT_DRV_B = 1;
  SHFMT_ID_DEFAULT = $FFFF;
  SHFMT_OPT_QUICKFORMAT = 0;
  SHFMT_OPT_FULLFORMAT = 1;
  SHFMT_OPT_SYSONLY = 2;
  SHFMT_ERROR = -1;
  SHFMT_CANCEL = -2;
  SHFMT_NOFORMAT = -3;

procedure TForm1.Button1Click(Sender: TObject);
var
  FmtRes: longint;
begin
  try
    FmtRes := ShFormatDrive(Handle, SHFMT_DRV_A, SHFMT_ID_DEFAULT,
                            SHFMT_OPT_QUICKFORMAT);
    case FmtRes of
        SHFMT_ERROR:    ShowMessage('Error formatting the drive');
        SHFMT_CANCEL:   ShowMessage('User canceled formatting the drive');
        SHFMT_NOFORMAT: ShowMessage('No Format')
      else
        ShowMessage('Disk has been formatted');
    end;
  except
  end;
end;