While CCleaner could be the best tool for cleaning Windows, it's not ideal for the novice user since it tampers with the system's registry. Users need to have some idea of what they're doing with CCleaner before making changes that could cause significant problems in Windows 7.
In a nutshell, CCleaner could be considered a bundled software package, offering a plethora of options, including removing unused and old entries in the registry, cleaning out browser history and local cache, eliminating stored temp files, and more. It's also quite fast and is spyware- and adware-free, making it an ideal tool to download for Windows 7.
Download: CCleaner 2.35.1223