UNIX isn't the best thing for single-user environments... sorry.
It's good that OS X is, for the most part, abstracted from the piddlings of UNIX, but it's still under there, and it's still as unforgiving as it ever was.
As for a password reset util... yes. it's there on the OS X install disc. After all, they intend this OS for home users as well, you know.
What happened with the password is unknown. I went to change my pw as I do occasionally, and afterward, I couldn't login anymore.
Re: entering "single-user mode", it would be nice if you could install it and never have any user accounts, no user-level security, none of it. It sounds odd, but coming from the classic OS, it's a little bit of a step backward to suddenly be inconvenienced by this.
I can't delete the file?!? WHAT?!?
The last time I installed OS X, it was when I went from 10.1.5 to 10.2, and I used "archive and install". This moved all the previous system files into a folder on the HD and then installed the system clean. You can then toss the old system folder in the trash.
No, you can't, because the folder is owned by root. By default, the root user isn't enabled. You can't login as root at all. The user doesn't exist. You have to enable it manually. It sounds odd, but it's something that comes from NeXT (NeXT and OS X don't expect you to think about UNIX. you're very well shielded from it).
It's little crappy things like that. but it's a trade-off that has to be made I guess. Now, however, I'm going to worry about my password... if I change it, will it break everything again?
All is well now. Psyjax and I had a go at seeing what we could do, but it wouldn't budge. Something got mossed up and wouldn't go back together, so I tossed all my programs and files onto the G5 via firewire and just erased and reinstalled.
So it's all good now