Boot failed from Hard drive

Dear all:

My ubuntu is dead sunddenlly. It seems that can't boot from Hard disk.
Maybe someone would like to give his advice.
When I put an Ubuntu installation CD , it can boot from the CD.
And I selected the menu to 'check harddisk' , 'check memory', it pass the testings.
So the hard drive seems have no problem on hardware.

So I try to boot from live CD.
After it login, It shows that it can't mount the hard disk.
The message is something like this.
---------------------------------------------------
mount: wrong fs type, bad option, bad superblock on /dev/mapper/my_vol
missing codepage or helper program, or other error.
In some case, useful info is found in syslog - try
dmesg | tail or so
---------------------------------------------------
And the message of dmesg | tail is:
[ 1536.013027] sd 0:0:0:0: [sda] Unhandled sense code
[ 1536.013031] sd 0:0:0:0: [sda] Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE
[ 1536.013037] sd 0:0:0:0: [sda] Sense Key : Medium Error [current] [descriptor]
[ 1536.013044] Descriptor sense data with sense descriptors (in hex):
[ 1536.013048] 72 03 11 04 00 00 00 0c 00 0a 80 00 00 00 00 00
[ 1536.013065] 00 00 21 4f
[ 1536.013071] sd 0:0:0:0: [sda] Add. Sense: Unrecovered read error - auto reallocate failed
[ 1536.013081] end_request: I/O error, dev sda, sector 8527
[ 1536.013117] ata1: EH complete
[ 1536.013363] EXT4-fs (sda1): no journal found

The Hard drive has only one OS ubuntu. So the environment should be quite clean.
It works fine 2 days ago but now it's dead sunddenlly.

It 's possible that I can use Ubuntu installtion CD to recover the system?
Any suggestion is welcome!

Thanks!

BR,
Stone.