This isn't the most feature-packed Windows optimization utility but we found it one of the easiest to control. Advanced WindowsCare Personal's simple interface offers two main options: Repair and Repair And Optimize. The former fixes Registry entries and cleans out your operating system. The latter does the same thing and tweaks Windows for maximum performance.
If you run into trouble, the Restoration option can return your system to its original configuration. The Advanced menu provides fine control over repairs and optimizations. Afterward, I noticed only one improvement, a reduced amount of used RAM, but that's not insignificant. However, the sparse descriptions of system problems may not satisfy seasoned users. And although the latest version of the app includes a help file, it's hardly extensive.
Nevertheless, if your system is doing its best turtle impersonation and you're considering reinstalling Windows, it wouldn't hurt to try this freeware package first. There's also a paid upgrade that offers more features, such as a run-in-background option, faster definition file updates, and tech support.