OpenGL, GUI question?

I am think on beginning a new 3d project, but this time I will need some GUI stuff, what you guys recomand?

Platform: Win32 (Win2000, XP, …)
Api: OpenGL, SDL(maybe), DirectX(Sound, Input), FMod(Sound), STL
Tools: Visual 7 (C++)

shell I use old Win32 api, MFC, C# style gui, ather gui libs that I don’t know some nice HTML will be nice? :stuck_out_tongue: