Here are few more things that I would like to add. Though you know that they are technical, create your documentation under the assumption that they don't know anything. Your document should help any primitive users.
1. Backup and recovery
i) Backup and Recovery methodology
ii)If you are using third-party software, remember to include
of any special features that you implemented at the time
of setup. Somthing like linking and etc
iii) If you have used RMAN, remeber to mention the catelog
username and the tablespaces and instances where the
catelogs are being stored. How they are being backed up
iv) A note on export and import options with example
2. Database Setup
i) Mention a word about the oratab file and the location
where it is stored.
ii) Distinguish between the ORACLE_HOME and
ORACLE_BASE. This would simplify lot of things
iii) Mention a word about the listener.ora and tnsnames.ora
and their purposes. How to stop and start them
iv) Is the Database in an archivelog mode
v) If there are any JOBS scheduled, mention what they do
What frequency it gets called. Also mention how to start
stop and check the status of it. Make note on that they
should check for its start status whenever they startup
the database instance.
i) Provide a brief description about the scripts and if it
accepts any parameters, provide a description about
them. Also provide an example on how to invoke them.
ii) Pros and Cons of the script
iii) If they are in the crontab, inform them about their
iv) If you have a source control, mention about its location
and how to check it out and check it in
i) What is an acceptable performance and what is not
ii) What are some simple measures that they could take
to solve them. List of views that they could use. Even
some simple queries.
i) What they should do when they start the Day
ii) Some obvious suggestions and solutions
i) Some informations on the tools that they could use to
do the day-to-day operations eg: OEM and etc
ii) How to start them and stop
iii) What are the do(s) and don't(s)
i) If you have metalink support, provide the URL and also
instruct them on how to create the TAR and etc
ii) Some good books/documentation for them to refer
iii) Some links for the references
iv) Some helpfull free support forum sites and etc
Hope these would help you to prepare your hand over documentation.