I've seen it done in a few rom hacks, but in the intro editing programs I've seen, they only allow you to skip portions of the oak intro and the intro with the blue screen explaining the controls. I also haven't found an asm script that can do this. I figure it couldn't be too difficult; just repointing a few offsets in a hex editor that load those portions of the intro. Does anyone have any knowledge about accomplishing this?
If I remember correctly, and I'm not 100% sure, there used to be a program that could make it skip the intro automatically. Pretty easy, I'm just not sure what it was called.
GBA Intro Manager by diegoisawesome and IntroEd by Mewthree9000 don't allow you to remove the GameFreak or Gengar & Nidorino battle parts of the intro. I haven't seen any other programs like them. Let me know if you remember / find one!
Do you know if there is a way to also skip past the black and white game freak copyright screen in the beginning?
Try and get your hands on a copy of Knizz's IDB and IDA, it would help you with these kinds of things. As for the BG itself, you could nop the tileset/tilemap commit to memory. Alternatively you could just make the entire BG black by following some boot screen editing tutorial.