I love this thread, can you keep it up a little longer? (I mean the the great advice)
If you're asking this question in earnest, I'll reply in kind:
I would generally shoot this type of photography with either a 50mm, 60mm, 85mm, or 105mm lens (DX or FX). I would want some foreshortening, but no exaggerated perspective, and no noticable barrel distortion (note that a 35mm lens on a DX body will still exhibit some barrel distortion, just as a 50mm lens on an FX body would). The main thing that will determine your longest usable focal length is the maximum subject-to-camera distance your shooting space allows. Determine which lens still allows you to frame a head-to-toe within the constraints of your space.
If you're including the space (e.g., a bedroom) as a significant part of the composition, where your subject's scale is half- to one-quarter of the frame, then you could go wider: 35mm, or even 24mm (FX). As long as you're far enough away, and your subject is nearer the center of the frame, and not near the edges, they should look fine.
As for lighting, you could go hard or soft. The convention, of course, is soft. The softer the better. I think almost everything looks better back- or three-quarter lit. A soft three-quarter back "key" with a lower-level (half- to full-stop) soft fill always looks nice. However, there's nothing wrong with hard three-quarter kicks or backs either. Another option is to light with practicals only (e.g., table lamp, candles, etc.), or with practicals and some bounced, umbrella-ed, or softboxed strobe for fill.