IN general, I would say to just be clear about the state that the system is in.
For example: Dell laptop, (various specs) running Windows Vista (original install) boot disks included.
Mac laptop, (various specs) running 10.6.5 (up-to-date-installation) boot disks included, also installed -
OpenOffice, Chrome, Flamingvixen, VLC, TeXshop, Gimp, Python 2.7 installed with Tc/Tkl functionality, most
recent developer tools.
That way, the user knows what's on it, and what they need to do (or should, if they are buying a used laptop).
If I'm selling or giving away a computer, what I would usually do is reformat the hard-disk completely, re-install the operating system from boot disk with a generic user account and password, bring it up-to date, and re-download some common 3rd party free-ware stuff, like Gimp and VLC. I hand over the computer, original boot disks, manuals, etc, and after that it's no longer my problem - if they need sys-admin duties, it's up to them to learn how to do it themselves, or get someone else to do it.
For family, I would probably only give it to someone for whom I'd be willing to do some set-up stuff, and who I'd trust not to abuse the privilege.