const
REGISTERKEY = '(например: auth)';

function _SaveData: Boolean;
var
  Reg: TRegistry;
begin
  Reg:= TRegistry.Create;
  Reg.RootKey:= HKEY_CURRENT_USER;
  if not Reg.KeyExists('Software\Software By m0nr\' + REGISTERKEY) then
  begin
    Reg.CreateKey('Software\Software By m0nr\' + REGISTERKEY);
  end;
  Reg.OpenKey('Software\Software By m0nr\' + REGISTERKEY, False);
  Reg.WriteString('Login', StringToBytes(Form1.Edt1.Text));
  Reg.WriteString('Pass', StringToBytes(Form1.Edt2.Text));
  Reg.CloseKey;
  Reg.Free;
end;

if (проверка) then  begin
if sCheckBox1.Checked then begin
   _SaveData; end;
<какой-то код>
end else  begin
  ShowMessage(Ошибочка); end;

function _GetData: Boolean;
var
  Reg: TRegistry;
begin
  Reg:= TRegistry.Create;
  Reg.RootKey:= HKEY_CURRENT_USER;
  if Reg.KeyExists('Software\Software By m0nr\' + REGISTERKEY) then
  begin
    Reg.OpenKey('Software\Software By m0nr\' + REGISTERKEY, False);
    Form1.Edt1.Text:= BytesToString(Reg.ReadString('Login'));
    Form1.Edt2.Text:= BytesToString(Reg.ReadString('Pass'));
  end;
  Reg.CloseKey;
  Reg.Free;
end;

procedure TForm1.FormCreate(Sender: TObject);
begin
_GetData;
end;