I am still not 100% clear as to how to decide the FILL FACTOR.

My understanding was that if you have a high input rate into a table then the indices need a lower fill factor (whatever lower may be).  If your tables are virtually read only then you can get away with a much higher FILL FACTOR.

If I look at the value for my server using sp_configure this returns zero so I am not sure what this means.

I could also do with an idiots definition of PAD_INDEX.