Just a recommendation...
1) Disk Clean up.
2) Defrag.
3) Update your malware protection.
4) Turn off System Restore...Boot into Safe Mode.
5) Run full system scans (inSafe Mode) with your malware protection software...fix or delete any issues.
6) Boot Windows normally.
7) Turn System Restore back on.
Again...run full system scans with you malware protection software.
Post your results, please?