Quoted from gdonovan:
So where would you start? My thoughts are a good cleaning of the area, upgrade the reset generator circuit per pinwiki and replace anything obviously corroded?
Yup, use zep as a first pass for cleaning, rinse thoroughly, then desolder the affected parts, sand the affected traces (removing the mask from any affected copper), use zep again to clean off the remaining alkaline, rinse thoroughly, blow dry with an air compressor, then air dry, then repopulate the board, and seal exposed traces with nail polish.
You can't really trust anything on that board diagnostically without addressing the corrosion.