Play Asia recently did an interview with Shigeru Miyamoto where he reveals some interesting bits of informations such as how he came up with Mario:
SM: We had to draw Mario as a small character and at the same time, we had to make him look human. To do that, we needed to draw a distinctive feature for him, such as giving him a big nose. We gave him a moustache so that we didn't need to draw a mouth. It is difficult to show facial expressions with small characters. We gave him big hands. Since we were trying to create something distinctive in the character, it was natural to draw something like that. First, we created Mario with dots, putting together these distinctive features. Then I finalized with a drawing to show a final image of the character. So I didn't have any special theory behind the making of Mario. He evolved over the development process, followed by a final drawing of what I wanted him to look like.
And about getting women more interested in video games:
... My wife does not play any kind of games. I have tried to make her interested with various games like Tetris, but she has never showed interest, until recently. But we're beginning to tear down the walls, starting with the Nintendo DS games. It was fun to watch. Although we have not gathered figures about this, I think games such as Wii Sports can interest women. Hopefully women will begin to enjoy games more. I think our target will be mothers. In a common family with a mother, father and children, I think mothers take the initiative in family entertainment and I think they would respond well to the Wii. And we might go as far as saying that we designed the Wii to that effect -- as something that mothers would want to buy.
Source: CNN