That's kinda odd that the old backups were a week old and older. That may mean the entry;
Name Data
ScanRegistry C:\WINDOWS\Scanregw.exe /autorun
has been missing from the;
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Run
key in the REG.
check also that SCANREGW.EXE exists in C:\WINDOWS
The normally compressed Backups are in the C:\WINDOWS\Sysbckup folder (hidden) with names Rb000.cab, Rb001, Rb002 etc...and each should contain SYSTEM.DAT, USER.DAT, SYSTEM.INI and WIN.INI
and are automatically created "One per Day" (24hr period - not each time Win is started). You can force newer backups 2 ways -
1 way (easiest) is Start > Run SCANREGW
...another is Start > Run MSinfo32 > Tools Menu > Registry Checker. Then check the dates/times of the Rb00x.cab files in SYSBCKUP, just before restoring so you get an idea of which Rb00x.cab file you want to choose. (this helps when you've recently manually created 3-5 backups using Scanregw.exe over say 2 days time).
Suggest you fix ScanRegistry in REG and you will see it also in Start > Run MSCONFIG > Startup Tab
You can try to import the whole registry in DOS mode as I described earlier, but I can't guarantee it will work using a Full Registry as you intend to do. It's possible there's the 64K file size limit, and or some kind of error when 'creating' your actual Backup.reg file. I have successfully Renamed System.dat and User,dat (hidden in C:\WINDOWS) to .xxx and restored them back when I got in binds in the past. So if something goes awry, just rename them back in DOS to .DAT and then Reset the Hidden and Read Only attributes with
Attrib +r +h SYSTEM.DAT
Attrib +r +h USER.DAT
The Scanreg /Restore works like a charm though and also backs up SYSTEM.INI and WIN,INI in case an App installed something nasty there too.
TT4U
Notification:
These are just my thoughts....and should be carefully measured against other opinions.
Backup All Important Data/Docs