Nintendo would go back to releasing awesome games for the Wii and Ds, and overall being as awesome as they used to be.
There would be a new 2d Metroid in the vein of Super Metroid.
Super Mario Universe. Yes, the idea's been done very much, but it's one of those classic things that is the very structure of video games. While we're at it, Super Mario interdimensional epicness.
Half-Life 2: Episode 3 with the portal gun and Portal 2.
Elite Beat Agents 2 (for the sake of dreaming, Elite Beat SOS Brigade. It's an organization to bring excitement to the world, it could work!)
New Ace Attorney.
And some other stuff.
Yeah, I dream too much.