PCAnalyzer is a powerful but small tool that analyzes Registry keys for suspicious values. The tool is comprised of three main features: Registry Scan and Fix, Processes management and Undeletable files.
The first feature scans and removes entries that may put your machine at risk. The process management tool keeps an eye on suspicious entries and undeletable files lets you know which files cannot or maybe should not be removed.
Note that if you can't fix a Key value, it probably depends on Key permissions. If you have trouble understanding the full registry report, the developer advises sending it to an advanced user for advice.