Sysinternals Suite is a full-featured pack of system utilities that cover a wide range of functions and needs and which are especially addressed at expert users and system administrators.
Of course, this doesn't mean that average users can't take advantage of Sysinternals Suite's more than 60 different tools included in the package. Simply bear in mind that they are not designed to be particularly easy to use, but just useful and straight to the point. Also, Sysinternals Suite's featured utilities are presented as a ZIP archive with all the standalone files, rather than under a single interface which would have been definitely easier.
That said, the truth is that Sysinternals Suite is a very complete suite with all sorts of tools. Many of them include command-line controls, and most of them enable you to take full control of the way the whole system works, plus analyzing everything that's going on and preventing any malware from running without your knowledge.
In spite of not being very user-friendly, the Sysinternals Suite is still a very valuable piece of software with a rich collection of system tools and tweaks.