It sounds like Windows restored a very old registry because ScanRegistry was not enabled in msconfig and making regular backups.
The registry replaced may still be on the drive if we can get at it. The command scanreg /fix might be able to repair it if we can get it loaded.
Here's what I want you to do.
1 -- create a new folder on the c:\drive and call it: regbak
2 -- do a Find Files for rb* (have subfolders checked). They should be found in the c:\windows\sysbckup folder. Maximize the Find Files Window, and note full name and "modified" date of each file
3 -- right click on an rb....cab file you find and select "copy".
4 -- open your regbak folder, right click on an empty space and select "paste". Continue until all the rb prefixed files are copied there.
5 -- let me know the full name and date of each of those files.
>> ps: pay special attention to anything named "rbbad", that would likely be the original registry windows replaced.
+++++++++++++++++++++++++++++++++++
This is going to be part 2 of the restoration procedure. You can proceed with it if the above went as expected and you feel comfortable with the instructions, or report back first.
1 -- Once you have the rbbad cab file copied to regbak use Winzip if you have it to extract the files. (Right Click on the cab file and see if you have "extract" in the Right Click menu)
2 -- The cab will contain 4 files, win.ini, system.ini, system.dat and user.dat. All these should be extracted to c:\regbak (make sure they go there and not to a separate folder, you may have to enter the path manually)
3 -- Once the files have been extracted, right click on both the system.dat and user.dat files, select Properties and remove the system and hidden attributes (you will need "show all files" selected in Folder Options > View to see these), then close the folder and restart in MS-DOS mode. You should now be at a c:\windows> prompt
4 -- At the prompt type exactly each bold line and press enter after each line. After each "copy" line, you should receive a prompt to overwrite. Type 'y' and enter.
attrib -r -s -h *.dat
copy c:\regbak\system.ini
copy c:\regbak\win.ini
copy c:\regback\system.dat
copy c:\regback\user.dat
scanreg /fix
If all went well, scanreg /fix should run and prompt you that it has repaired your registry. Let us know what happens when you restart after this.