Well, you need the media for that. And you must make that yourself. But Darkbasic can put it all together and create something very nice.
The voice is something you have to record yourself and the animation you have to draw or model yourself. That is how it works. Everywhere.
Dark basic puts it together and you have your intro.
And perhaps even a whole game attached to it. But again: you have to do the models and other art. Offcourse there are some primitives you can play with.
As for your second question. It looks as nice as you make it. If you put two hours work in it, it looks like two hours work. If you put two weeks in it, you can see that.
Darkbasic can produce whatever you want, but you have to do it. That's how DB and any other language works. Only DB makes it easy to put things together.
Hope that was the answer you wanted?
By steel will thy flesh divide