См. пример.
Пример :

             procedure TForm1.Button1Click(Sender: TObject); 

             begin 

               SendMessage(FindWindow('Progman', 'Program Manager'), 

                           WM_COMMAND, 

                           $A065, 

                           0); 

             end; 

В приведенном примере определяется включен ли режим "Full Window Drag" (перерисовки всего окна при перемещении)
Пример :

             procedure TForm1.Button1Click(Sender: TObject); 

             var 

               b : bool; 

             begin 

               SystemParametersInfo(SPI_GETDRAGFULLWINDOWS, 0, @b, 0); 

               if not b then 

                 ShowMessage('Full Window Drag is not enabled') else 

                 ShowMessage('Full Window Drag is enabled'); 

             end; 

Пример работает и для Win32и для Win16.

             uses 

               Registry, {For Win32} 

               IniFiles; {For Win16} 

             {$IFNDEF WIN32} 

               const MAX_PATH = 144; 

             {$ENDIF} 

             {For Win32} 

             procedure TForm1.Button1Click(Sender: TObject); 

             var 

               reg: TRegistry; 

             begin 

               reg := TRegistry.Create; 

               reg.RootKey := HKEY_LOCAL_MACHINE; 

               reg.LazyWrite := false; 

               reg.OpenKey('Software\Microsoft\Windows\CurrentVersion\Run', 

                           false); 

               reg.WriteString('My App', Application.ExeName); 

               reg.CloseKey; 

               reg.free; 

             end; 

             {For Win16} 

             procedure TForm1.Button2Click(Sender: TObject); 

             var 

               WinIni : TIniFile; 

               WinIniFileName : array[0..MAX_PATH] of char; 

               s : string; 

             begin 

               GetWindowsDirectory(WinIniFileName, sizeof(WinIniFileName)); 

               StrCat(WinIniFileName, '\win.ini'); 

               WinIni := TIniFile.Create(WinIniFileName); 

               s := WinIni.ReadString('windows', 

                                      'run', 

                                      ''); 

               if s = '' then 

                 s := Application.ExeName else 

                 s := s + ';' + Application.ExeName; 

               WinIni.WriteString('windows', 

                                  'run', 

                                  s); 

               WinIni.Free; 

             end; 

Следующий пример изменяет приоритет приложения. Изменение приоритета следует использовать с осторожностью - т.к. присвоение слишком высокого приоритета может привети к медленной работе остальных программ и системы в целом. См. Win32 help for SetThreadPriority() function.
Пример :

             procedure TForm1.Button1Click(Sender: TObject); 

             var 

               ProcessID : DWORD; 

               ProcessHandle : THandle; 

               ThreadHandle : THandle; 

             begin 

               ProcessID := GetCurrentProcessID; 

               ProcessHandle := OpenProcess(PROCESS_SET_INFORMATION, 

                                            false, 

                                            ProcessID); 

               SetPriorityClass(ProcessHandle, REALTIME_PRIORITY_CLASS); 

               ThreadHandle := GetCurrentThread; 

               SetThreadPriority(ThreadHandle, THREAD_PRIORITY_TIME_CRITICAL); 

             end;