Explorer, Continued

If an application becomes unresponsive, its window fades out of sight...

...shortly thereafter, Windows displays an error message and asks you if you'd like to restart the program.

Right after it starts up, defrag indicates if a disk defragmentation is necessary. You can even instruct Windows to handle defragmentation automatically.

During the defragmentation process, Windows throttles itself back and displays a status indicator.

Windows won't restart? In the future, this window will explain the cause.