During startup Windows automatically loads many programs into memory. Some of them works in a background, some waits for user action as an icon on the taskbar. All of them uses computer's resources (memory, CPU time...) With WSM you can easily manage all these programs. Create "profiles" - groups of these programs (here called startup elements) During system startup just select which profile you want to run.
PROTECTION
With WSM you can restrict access to your Windows system. You can use standard password protection, but WSM delivers you an unique feature - Kids Protection System (KPS). With KPS you can create a list of items (applications, movie clips or any other documents). During startup WSM prompts for password. Without valid password it is only possible to run one item from the list. It is impossible to run anything else.
TWEAKING
With WSM you can run any application as the only thread of the system (even without shell such as Explorer). It gives you as much memory and other system resources as possible. It also makes system stability higher.