If System Restore
is working you can always try using it. Whether it will be successful or not depends on the malware infection not disabling that feature and whether malicious files have already been backed up to your restore points. When malware is present on the system, it can be included in your restore points so using System Restore on an infected system may restore other malware-infected files
if they are present. Generally its better to leave it alone until the machine is clean and stable. However, in some cases, using System Restore may return some system stability if you are having problems running disinfection tools or booting up.
Keep in mind that if you are able to successfully use System Restore to return to a previous state there is no guarantee
your computer will not still be infected. As such, you should immediately perform scans with your anti-virus and anti-malware tools afterwards.