Windows XP Crash – System File Missing

My Compaq Presario 8000 with windows XP took a power hit and doesnot boot up. I get a message stating that a file is corrupt or missing
\windows\system32\config\system. I am assuming that I will need to load a start up CD ROM and the system willr evert back to its original configuration. I donot have a recent back up of the system configuration.

Is there a way I can load the start up CDROM and still retain the files and applications I have loaded on the PC? Thanks