Windows 2000 Manual repair & SP4

Hi
My win2k DC had some data corruption. Wins & the paging file were some of the errors I saw. Hence I did a manual repair with the ERD. I choosed to repair only the system files.

Q1. Should one choose to repair all system files or only certain files such as DLL or SYS. Is it recommended to do a fast repair.

After doing a manual repair My win2k DC had this error “security Account Manager initialization failed. Directory service cannot start. Error status 0xc00002e1. Please click OK to shutdown & reboot to directory service mode”

I could not find any useful info on the MS KB. SO I did a restore of the server & AD from the tape backup.

Q1. I have now applied SP4. Must I re-apply all the Hotfixes after SP4.
Q2. Any solutions for the above error