I've been advised by salesmen to stick with my old (nay, venerable!) screw driven f/1.8 AF 50mm which cost me £40 a good few years ago. Since the D7000 has the in body AF motor, I would recommend that version for bang for buck.
Thanks for the link Minnnt, pingu666 i have been looking at the 60mm, but i do prefer the 50mm.
Thats interesting Nod, i've been told to go for the G