Hello again Mint forum,
My problem was I did not Google enough for the solution. I fixed my problem with this web site: http://ubuntuforums.org/showthread.php?t=1309554
Now just before the desktop launches, I am greeted with a box asking me which user do I wish to log into, either mint (live session user), or user roy.
but this is a quote of what it said by juliopjuliop:
Re: Disable Automatic Login on Karmic USB Install
Hi, after many hours of pacience i have managed to come up with a solution to this problem. First i found out the root of the issue is that a script in initrd.lz actually creates the autologin instance(/etc/gdm/custom.conf) for ubuntu user in a livecd, this script is called "15autologin" and is located in the livecd, in the directory "/usr/share/initramfs-tools/scripts/casper-bottom/" the way i fixed this was i unpacked the squashfs file and chrooted in, then edited 15autologin file to set automaticlogin=true to false and i also changed the timeout option to false. Then i went ahead and rebuilt the initrd.lz with this command "mkinitramfs -o /initrd.lz 2.6.31-11-generic" wich made a new file called initrd.lz in the root of the squashfs, then i proceded to close the chroot and overwrite the /casper/initrd.lz in my liveusb with the newly generated one, and booted it up and vuala it showed me the login screen. hope this helped.
Also in theory this could work from within your liveusb just modifying the file 15autologin temporarily in the live environement and using "mkinitramfs -o /initrd.lz 2.6.31-11-generic" then you will have too copy it too another usb or onto your harddrive and then bootup into another os and overwrite it as you cannot overwrite your initrd.lz in your usb as its mounted as a cd.
PS: i would gladly upload the modified initrd.lz so you wont have to go through all this hassle, but im not sure if i can.
I think I could have accomplished the same thing by editing the initrd.lz that is on my USB stick directly. I *think* all of the information in /usr/share/initramfs-tools/scripts/casper-bottom is updated from the actual initrd.lz on the USB stck each time you reboot. If I'm wrong about that, please let me know.
I believe when Mint is installed directly onto a hard drive, the install script in /usr/share/ubiquity/install.py might do this same thing differently because I doubt if re-creating the initrd.gl file is part of the standard installation process.
All the best,