I have onyx downloaded on my mac to help keep my computer clean, but im nervous to delete the wrong stuff so in the maintenance tab (where u can delete "system" "user" "fonts" etc) what should i not delete and leave alone
What version are you using? In the latest version for Snow Leopard, Ver. 2.3.1, the items you mentioned "system" "user" "fonts" etc." are located in the "Cleaning" section, and they all refer to the related caches, not "system" "user" or "font" files themseves.
In that cleaning section, all of the ones you mentioned, "system" "user" "fonts", require a reboot after you delete those caches, while using the "Internet, Logs, or/and "Misc." tabs to delete those related caches does not require a reboot.
In regard to correct usage, I would suggest you will rarely need to use the ones you mentioned, and deleting the "Fonts" caches requires the re-use of Font Book to re-disable any disabled fonts. Use these only if you suspect an issue is related/due to these caches.
A quick and easy tune-up can be done using the "Automation" tab, and selecting only the bottom 3 items in the "Cleaning" section and maybe the "Execute Maintenance Scripts" in the "Maintenance" section.
This is of course not really necessary, the system will do it automatically, but it does delete about 700 files on my system, so I do it before running a backup at the end of a workday.


