No nba games default settings are realistic, 2k8 is harder to fix than live this year however (In live you can get realistic box scores easily, in 2k it's not as easy to achieve)
http://www.sportsgamer.com/forums/forum852/
I use those sliders and playbooks on live 08 (I can't use the roster because I have ps3 and the roster is for 360, so when I get around to changing the roster manually it will be better)
But that makes the gameplay a lot better and the teams play like them selves, and the box scores are more realistic than you can believe.
(If only I could get that roster file for ps3 though, it would take forever to do all that manually.)