system restore is a bad way of protecting your PC against virus.
The virus often hides in system restore it cannot be deleted or scannned by the Peotection systems as the restore files are "protected by windows".
So scan and find the virus, delete it and then do a system restore just puts the virus back into your system.
It is always recomended if you have a virus to switch off system restore to delete all the restore points, rescan to make sure the virus is gone and then switch restore back on.
In your case I suspect you have a corrupt restore that is causing your problem.
Switch off system restore
then boot to safe mode and delete the system volume information folders click here
Reboot and then see if you can switch restore back on