Silly question: when you're eyeballing the Wii, is the power button solid red or does the Wii appear dead? Black screen suggests you've successfully turned it on, but then you mention the power adapter. You must unplug it BOTH from the Wii and from the wall. Wait 5 minutes. Plug it back in. That's only if the Wii is perceived as dead/no power. Power and black screen, that's another issue entirely. Which is it?