how to login as a root in graphical mode for GNOME

It's not advised, but to login with root just create a password for it with this command in the terminal
sudo passwd
then go to System->Administration->Login Window and under the Security tab check the "Allow local system administrator login"
You'll be able to login to root after that.

I have tried this but i need gui access for particular multimedia application.
My system does not allow me to change any setting in admin tab but Still i am Admin user ( I can use sudo and change cofigurations)
If you know how to enable this let me know. I know in some file we need to change AllowRootUser variable to true. I am not able to find that file. I am using GNOME.

On console type

sudo nautilus

And it will grant root priviliges to nautilus, open up in /root with full access to all files/folders

Take note:
That running programs with root privileges can be potentially dangerous as there is no protection for the user. Take due care and always understand what you are doing before messing with important files and remember to back up!

Goodluck!

There's a difference between an Admin user (normal user, not a guest account) and SuperUser/Root. To use the features in the menu from the top taskbar

System - Administration

It asks for a password that is just your normal user one, not the SuperUser/Root password - so its the same password you use for "sudo" commands but not the one you use for "su"

Hope this helps cos i'm a bit unclear what you're asking. Perhaps this might help
http://www.psychocats.net/ubuntu/resetpassword

Regards from
Tom :)

Thanks Christopher Lunsford, that solved my question.

hey geeks, that was /etc/gdm/gdm.conf file i was looking for.
Thanks Lot.
All the best to you all.

:) heheheh. Knowing the problem is half the solution. Glad we managed to get a right answer in there for you.

Welcome to Linux
Regards from
Tom :)