|Some addtional suggestions; not the least as likely you do not have the W2K CD etc...?|
Ensure that the user(s) copy their personal files etc. to external storage - another HD or at least optical-media; and, if the lattter, verfiy that can be access OK on at least one other system. Safeguards them all in event of system failures...?
Also extract all software keys from the installation as is once all updated etc.
If you go:
Start\run\ and type in: msinfo32 and press enter/return
you will get a list of what's installed etc... Dig around in there you can find the keys for assorted software.
Also Belarc (Advisor) will do the same (google for it?).
Useful to have theeeeeese keys etc. externally - hard copy in a safe place; and maybe affixed to the case (underneath too)?
Likewise - if no W2K CD or other software etc... consider either a true backup of the installation to external media (optical is usually best here) - can be done from within W2K itself; or (I think a better approach) make an image of the drive - and this to be bootable as well. Acronis make an excellent utility to this end; and there are others similar too...
Then if the system truly crashes... you can restore a working model from the backup or image - whichever?
Likely on the drive you will find the i386 folder - and if so - copy it to optical media and keep safe... It may allow another way to re-install within limits in event of problems...
Label any/all disks you make accordingly; and include keys as appropriate on labels.
Being a Dell system it is equally possible it has a recovery partition (hidden) on the drive; usuall at the physical start of the drive - and I repeat it's hidden. This allows you restore the system to delivery status; but means all updates have to be re-applied... And all personal files etc are invariably lost in the restore process; which is why again copy them elsewhere (external storage) - regularly...
There will also be a Dell "tag" number on the case somewhere. Note it and keep it safe...). If you go to Dell site/support and enter that tag.. you go straight to support area for that model; and can find all manner of stuff about it - manuals, drivers and the like... You may also be able to acquire any missing re-install/restore disks if needs-be - possibly free or for a modest shipping/postage charge? Woth considering?
A wee bit to do to be safe for the future; but you have very viable and working system... so worth to do?