Recently i messed up my settings by deleting the /usr directory contents .... But to my relief i had a liveCd for my rescue and i could restart my LINUXMINT 13 (maya)cinnamon desktop edition... but to my surprise the majority of the settings were changed like :

1) none of my Windows Partition is being shown ( all the windows partition's were easily accessible before this blunder )

2) i had a hunch for cinnamon desktop edition and it was installed into my settings but now the default mint desktop is being shown ( at the same time i can't change my desktop settings from "preferences" menu .... its giving me no response )

i would be highly obliged if someone helps me out in this ( and please people i am a newbie in this linux environment !! )

Thanks in advance !!

Could you describe how you started up your system under the LiveCD? If your system lacks a lot of files, then the usual procedure of doing "chroot" to your system where it is mounted will just get you on the same broken system. It sounds like you are just running the LiveCD as the system, which would know nothing about the particular things you changed in your system. Tell us what you do within the LiveCD to be on your own system? Are you mounting anything?

You may need to re-install the system. How much of your personal data is on there that needs to be backed up?

The system settings are in /etc and /home/<user>. Programs and documentation are in /usr.

@skaperen : I used the liveCd to copy the missing folders of /usr to my mint partition .....
see when i deleted the usr directory then after startup the only thing that was visible to me was a terminal sort of thing at start up i.e nothing GUI as such .
then
i ran the mint livecd and mounted my linux partition and then copied the /usr sub-directories into the /usr of my mint partition .....
by doing so i managed to get the GUI part of Mint again on startup but with missing things like Missing ShutDown options missing my Cinnamon Desktop missing my preferences control and many other settings

@Awesome Machine : but how to make use of them to get my previous settings back on the track ?? I a newbie buddy !!