It depends on if you want to just go to emails and contacs there are videos on how to unlock it
just press on it
it takes a while to unlock all the vids, but you've gotta complete the game.
to unlock movies you need to earn 550,000 monster points or more.
Go to youtube. Theres tons and tons of videos on how to.
you have to put in your code
You can unlock more music and instruments by playing the handbells, conducting, making your own videos, and going through the lessons. Once you make enough videos and get a high score on some of the games, you can unlock quite a few things.
You cannot unlock Shadow in Sonic Adventure DX. Videos from YouTube that show him in SADX are hacks.
If you keep playing games, making videos etc you will eventually unlock it.
Two videos from Youtube that relate to your question can be found below.
they unlock videos and artwork
Wario is not in New Super Mario Bros.