Lots of stuff about ohci1394.sys on Google - seems to be a not uncommon problem 'tho never experienced it myself.
ohci1394.sys is the Firewire Host Controller System Driver
Did you try this?
"Use the “Windows Repair function on the install disk” this works for both XP and Vista. Put your XP or Vista disk into your CD drive and restart your system. This will start the XP installation process. When you come to the screen that asks if you want to install XP or if you would like to “Repair” XP, choose Repair. This will open the repair console command prompt go then at the prompt, enter this “CHKDSK C:/R” (or CHKDSK /R to repair the OS on the default HDD partition e.g. C
). Now hit “Enter”. The repair should now start. Allow it to run until it stops. This can take some time, so be patient."
Mac