What is the Wii doing during the white warning screen ?

[GodRays]

As the title says, what's going on during all that time, is the Wii actually loading the game or is it just showing those screens ?

I haven't found a way to get rid of it in the real console, but what about in the emulator ?

P.S.: I have searched the forum and couldn't find any discussions for this, unless I used the wrong keywords.