I would like to delete users, but I want to keep the record. In other word, I don't want to change users of Reporter or Assignee field for closed issues. Is there any way to do this?
The better solution is to deactivate a user, this will mean that their history will remain and you don't need to worry about reallocating issues. You can deactivate a user in OnDemand by removing application access, which you can find by going to administration->users->application access. If you remove the user from all applications then they won't be able to log in and won't contribute to your license count.
More information on application access can be found at:
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