Victoria 2.0 from DAZ (www.daz3d.com) is probably the most versatile model you can get, it has a multitude of facial morphs and expressions that you can use. You also need a photorealistic texture. DAZ's own texture for Vicky is good and you can find several very good ones on this site. A good tip is to take a look at the textures made by Stefyzz and Magnet, search on their names in the Renderosity MarketPlace.