corrupt C:\windows\system32\config\

i have an error loading winxp
corrupt file in C:\windows\system32\config\
file names are default & system
i have had to install windows in a dual boot atmos because of a quick repair situation, so my boot options are 1 = windows, 2= windows2
these are my directories on the c drive
i cannot access the windows2 directory in dos
i need someone with experience in repairing the file system in msdos mode