That logout chech-box I uncheck at 1st reboot/logout after a install.
I also want to know a way to check how many programs or services autostarts every booting times in case they don't appear in "Settings > session and startup".
If your on the Ubuntu based Xfce (or any DE) theirs a handy program called 'BUM' (boot Up manager) that will tell what 'Run-Time' services will run. And their are other run-time editors in repos also.
For other apps it's easy to see whats running with a task-manager and kill process and resave session for future logins.
P.S. their's also a 'boot-benchmark' tool some were talking about when I asked about boot speed of ubuntu vs debian. (I never used thou)