First thing - when you apply under the skilled migrant category, which I suspect you are thinking of since you mentioned the points system, you are applying for Residence, not PR. PR is a totally different visa that you only qualify for after living for at least two years on a Resident visa. There are not different categories of PR.
This
http://www.immigration.govt.nz/migra...nt/default.htm is the first place to look, then the How to Apply link from near the bottom of that page. However, rather than the points calculator, which can be misleading, I recommend looking here
http://www.immigration.govt.nz/opsmanual/6954.htm. SM6 has a chart of all possible points, and the other sections set out the detailed requirements for claiming under each heading.
If you have a skilled job, or offer, in NZ, you need a minimum of 100 points for your EOI to be selected. If you don't have a skilled job, or offer, you need at least 140 points.