Which antivirus program are you using ?
In Safe Mode all 3rd party programs are isolated so your antivirus program shouldn't have been loaded.
For this you can either boot up with the install disk and click on Repair your computer on the Install screen or boot up into the advanced boot options and select Repair your computer which will take you to the Recovery Environment (RE) to select System Restore.
However, before selecting System Restore should anything else be pending which could be blocking the restore operation, select Command Prompt and enter these cmds -
bcdedit |find "osdevice"
For clarity that is a Pipe symbol before find and is the uppercase of \
Then using whichever partition letter, as it may not always be c: - enter this cmd using your partition letter where I have used C:
dism.exe /image:C:\ /cleanup-image /revertpendingactions
Note the space before each /
Ignore anything about the scratch directory, but it should report the operation was successful.
Enter exit to close the cmd window and restart to effect then go back into that mode to select System Restore.
If that still fails then I think the best bet would be to go for a repair install.
If it's successful then try your restore points in normal or Safe Mode to see if they still work.
To back up your drivers folders, go Start - click on Computer and insert an USB flash drive.
Double click on Windows C: - double click on Windows then scroll down to System32 and double click on that.
You may need to use the vertical scroll bar in the left pane to see the USB drive which could be E:
Right click on each of the drivers folders in turn and drag them down to the USB drive where you'll get Copy to removable drive E: then Copy here where you will then see it copying.
Previously I had three drivers folders but on checking since a factory reset, I find I now only have two but the DriverStore one will be the largest - mine is 1.82GB.
When done, close up Drive E: - right click on the USB drive and select Eject to safely remove.
You can then proceed with the repair install.
To put them back into System32, just reverse the drag & drop procedure.