By lines of code, I expect that I've written more for Windows that I have for any other OS.

Much of my early development has been with C++ using MFC. I'm very familiar with Gdiplus. However, given that it doesn't use the GPU, I would only suggest that technology for minor graphic usage. In effort to get better performance, I've migrated much of what I've done with Gdiplus to OpenGL. Still, that approach is very dated and I wouldn't recommend it.

More recently, I've developed software with C# and .Net. Which is much much much better than MFC