followed how to dual boot with xp

and did nothing extra, but now cant start windows xp sp3 with error message of "disk read error has occured ctrl+alt+del to restart" my xp os is installed on C drive with 127 GB with two 80GB parition and when installing BT only allow me to install on the full Harddrive or C in that case DEV/SDA1 which i divided into 100gb for xp and 27gb for BT

boot with xp cd and chkdsk /r command give me one or more unrecoverable error.

What could i possible done to make it happen?