AidansDad
>.. one sme server I work with had a near complete hard drive failure.
>... I spent the day with it yesterday...
I'm interested to know why you don't insist on RAID1 drives at least.
Isn't your days time or whoever is paying you for it, worth more than the cost of a second drive ?
It will give you data security (with a redundant disk), when compared to the loss of data consequences of a drive failure in a single disk server !
>... how I backup and restore the existing users on the system.
>.... what files do I need to pull off the old drive then restore to the new install.
Answered many many many times, so search the forums eg on backup.
You can use the LAT (Lazy Admin Tools) contrib also (on a working system though).
Note that pulling certain files off an old server is not necessarily the answer as there is no one or two files alone that ONLY contain users info. The information you need is distributed across many different files (which are part of the standard backup).
It has also been answered before that it would be possible to create a contrib/code to selectively extract just users info for selective restore, but no one has developed that contrib yet, or been willing to pay a developer to create it.
What about backups, do you not have any for that system, if not then I would strongly suggest you put in place a good daily backup strategy for that organisation.