The only thing that fits the bill is C++ with the basic Win32 API that you're guaranteed ships with every version of Windows. But you'll still need to bundle th

The only thing that fits the bill is C++ with the basic Win32 API that you're guaranteed ships with every version of Windows. But you'll still need to bundle the Microsoft VisualC++ runtime installer. To save yourself from writing raw Win32, I would suggest WxWidgets. You can link statically to the library and compile in only what you need, keeping size manageable.