Díky. Někdo se mě ptá a má to takto:

HINSTANCE hInst;								// current instance
TCHAR szTitle[MAX_LOADSTRING];					// The title bar text
TCHAR szWindowClass[MAX_LOADSTRING];			// the main window class name
TCHAR szText[MAX_LOADSTRING];

int ColorR=0,ColorG=200,ColorB=255;

void SetDefalut(HWND hWnd);
void SetCervenou(HWND hWnd);
void SetZelenou(HWND hWnd);

void DrawWndContent (HWND hWnd, HDC hDc);
void DrawMousePointer (HWND hWnd, int x, int y);



LRESULT CALLBACK Title(HWND hDlg, UINT message, WPARAM wParam, LPARAM lParam)
{
	switch (message)
	{
	case WM_INITDIALOG:
		
		{
			HWND hEdit = GetDlgItem(hDlg,IDC_EDIT1);
			SetWindowText(hEdit, szText);
		}
		return TRUE;

	case WM_COMMAND:
		switch(LOWORD(wParam))
		{
			case IDCANCEL:
				EndDialog(hDlg, LOWORD(wParam));
				return TRUE;
			
			case IDOK:
				{
					HWND hEdit = GetDlgItem(hDlg, IDC_EDIT1);
					GetWindowText(hEdit,szText,MAX_LOADSTRING);
				}
			break;
		}

		if (LOWORD(wParam) == IDOK || LOWORD(wParam) == IDCANCEL) 
		{
			EndDialog(hDlg, LOWORD(wParam));
			return TRUE;
		}
		break;
	}
	return FALSE;
}



LRESULT CALLBACK About(HWND hWnd, UINT message, UINT wParam, UINT lParam)
{
	if (message == WM_COMMAND && (LOWORD(wParam) == IDOK))
	{
		EndDialog(hWnd, IDOK);
		return TRUE;
	}
	return FALSE;
}

LRESULT CALLBACK MyWndProc(HWND hWnd, UINT message, UINT wParam, UINT lParam)
{	
	int wmId;

	PAINTSTRUCT ps;
	HDC hdc;

    switch(message)
	{

	case WM_COMMAND:
		
		wmId = LOWORD(wParam);
		switch (wmId)
		{
		
		case IDM_ABOUT:
			DialogBox(hInst, MAKEINTRESOURCE(IDD_DIALOG1), hWnd, (DLGPROC)About);
			break;

				
		case IDM_EXIT:
		if(MessageBox(hWnd, "Chcete ukoncit aplikaci?","WinHello", MB_YESNO | MB_ICONQUESTION)==IDYES)
		{
			DestroyWindow(hWnd);
			break;
		}
			break;

		case IDM_SETTINGS_EDITTITLE:
			DialogBox(hInst, MAKEINTRESOURCE(IDD_DIALOG2), hWnd, (DLGPROC)Title); 
			InvalidateRect(hWnd, NULL, TRUE); // prekresleni okna
			break;


		case ID_DEFALUT:
				
			if(MessageBox(hWnd, "Opravdu chcete barvu změnit na původní?", "Změna barvy",MB_YESNO | MB_ICONQUESTION)==IDYES)
			{
				SetDefalut(hWnd);
			}
			break;

		case ID_RED:
					
			if(MessageBox(hWnd, "Opravdu chcete barvu změnit na červenou?", "Změna barvy",MB_YESNO | MB_ICONQUESTION)==IDYES)
			{
				SetCervenou(hWnd);
			}
			break;

		case ID_GREEN:
					
			if(MessageBox(hWnd, "Opravdu chcete barvu změnit na zelenou?", "Změna barvy",MB_YESNO | MB_ICONQUESTION)==IDYES)
			{
				SetZelenou(hWnd);
			}
			break;
		
		}
		return 0;
		

	case WM_PAINT:
		hdc = BeginPaint(hWnd, &ps);
		DrawWndContent (hWnd, hdc);
		EndPaint(hWnd, &ps);
		break;