Lens for movie making on Nikon d5100?

I have so many ideas of making lil movies that go along with some of my favorite songs- can anyone recommend a really great lens that can pick up a lot of depth. I have a vision of getting a good close up of someone's eyes, and then a torso of a person while they lay on the ground.

I want the picture to be sharp yet soft, but professional looking. Can anyone help me with this?

Also, i want to add visual effects to the video that i shoot, can anyone recommend a software where I could add shimmers of light on the model?

Sorry for so many out there questions, I've never really experimented with my nikon…

I would recommend something around a 24mm-70mm. I'm a canon guy and that's what'd I'd use. Sorry for the so-so answer. Good luck with your movies! I'm doing somewhat of the same thing!