The other items are mainly just general info. Date and Time are self explanatory. Processes reminds you of how many things are running; Sometimes you forget about hidden programs that you don't need such as screen savers, utilities, sound programs, etc.. (See Memory)

The main thing to use is the restart Windows. Windows now can run for weeks where you were lucky before to run for hours but it is still a good idea to restart the computer to reset things after a while. Some programs use some resources and don't return them to Windows even after they close; When you're not busy, restart Windows to reset things the way they started. (I try to restart every few days at least.)