Originally Posted by jeff80
Thank you for the help
Please let me know what are the important files on which I should work.
That's not the way to do it. Work on the functionality of the computer and the applications. For each situation where you want to install or configure something, you will discover the GUI tools and you will discover what files are relevant.
For example, /etc/X11/xorg.conf will make much more sense to you if you need to change your video setup. And /etc/fstab will make more sense if you want certain devices to mount automatically at boot time.
Oops, I gave you some filenames...
If you need to change how the computer starts, you might want to look at /etc/inittab and /etc/rc.d
There I go again.......