Applications like system preferences missing

Hey,
Yesterday I changed the password to the 1 admin account I then had. Unfortunately I forgot that password since after changing it I went out and got quite ******.
Today I managed to get a second admin account on my MacBook OS X 10.5.6 by doing
mount -uw/
rm /var/db/.AppleSetupDone
shutdown -h now
in single user mode.
But then the real trouble started. I wanted to delete the first admin account through system preferences but couldn't find system preferences in itself. Also other applications like Neo-Office, Firefox, PhotoBooth, etc were not accessible.
I think this is because I've dragged them out of the applications folder and put them on the desktop of the admin account that is now not accessible.And I can't access that previous admin account now either.
I've tried things like disk repair and software update but nothing seems to work. Even the commands fsck -yf and reboot failed me.

I've got a back-up of the really important stuff like my dissertation but I still have got loads of other stuff like music and movies that I don't want to loose by re-installing OS X (not that it would work since my cd-drive doesn't work anymore). Any idea's on how to handle this?
Thanks in advance,
D

Try this:

Log onto your new Admin account and turn on the "Root User" account. Then log on as "Root". That should give you access to both accounts and also the desktop of the account you can't access. You can then try to drag everything back in place and start over.

Here's how to turn on the Root user. Follow the instructions given for Leopard. LINK

If the above doesn't work, you may have to do an Archive and Install re-install. (Assuming you don't have a Time Machine backup.)

Thanks, but I can't access system preferences so I can't enable the root user.
Also can't do an archive and install since my MacBooks cd-drive doesn't work.