Trying To Reset Admin Password

I bought a second hand G5 Powermac and don't have the administrator's name or password. I went to the used book store and got a retail copy of leopard, 10.5 because it's running leopard, in order to reset the password. I'm trying to follow instructions on line and put the disk in, held down the D key, and now my options are install, optional installations and the instructions which don't tell me how to do it. How do I reset the password without reinstalling and possibly losing my files? Help, please!

I'm not getting a menu.

OK, thanks. I was afraid to go that far.

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It won't let me even get that far without an administrator's name and password. I clicked on install, and it wants that first.

I appreciate your help and patience. I tried again using the C key instead of the D, and selected the language. Then I got an agree to the license page, and next it told me I can't install because I have a newer version of the OS already. But I still didn't see the menu! I'm going to try again.

I found it, hidden in plain sight.

When I clicked on password reset, it gave me the choice of resetting the password on the disk or the hard drive. I chose the hard drive, and reset it. Then it gave a message saying:

Password saved. The password you entered has been saved for the user System Administrator (root). Resetting a user's password does not change the password for the user's log in keychain so it will not be unlocked automatically. Use keychain access to reset the password for the user's log in keychain. Then I hit agree, and to reset the Home Directory permissions and ACC's.

What does all that mean, and will I be able to download updates now? I don't know the former owner's name, can I just type in System Administrator (root) and the new password?

CRUMMY! I just tried adjusting the clock, and it still won't let me in to make changes!

I finally got it, and was able to do all the updates!!!

The trick was to type the word root for the administrator's name then use the new password that I put in when I reset it. Tomorrow maybe I'll give myself an administrator's account. It's getting late. Just thought I'd add this post to the thread in case someone else with the same problem reads this.