Comment Not necessary (Score 1) 208
I'm surprised only one other person pointed out almost none of that info is needed. Banks, courts, insurance, attorneys, brokers, all of them have procedures which negate passwords/PINS/all that info the executor of the estate typically doesn't know.
What you do want is to get way more copies of the death certificate than you imagine you'll ever need. The death certificate and the institution's forms will gain you legal access to everything. Accessing them improperly could lead to trouble.
(A list with passwords should be outdated in a matter of weeks when passwords are changed anyway, account numbers when accounts are closed/moved, etc. It's just quicker/easier to use the institutions process and doesn't ruffle any feathers.)