No .reg backup selected after CCleaner performed

Need help please as I ran CCleaner and did not select backup option....now shortly after computer boots into Windows, EVERYTHING freezes except for the mouse. Since backup option was not selected, no .reg file was saved/created in my documents to be able to merge and recover/restore back to normal. Can anyone suggest any resolution to restore everything back to normal before I ran CCleaner please?

System restore... do you have it turned on?

What operating system are you using?

Also are your antivirus and malware programs up to date and coming up clean after a scan?