You talk about the windows taskbar right?
Why does it disturb you, do you play in windowed mode so you see the taskbar while games are active?
Normally you play in fullscreen mode so the taskbar and all other windows stuff will be hidden for sure.
And due to this normally it's the other way around that the taskbar pops up in front of games :-)
Did you right click the taskbar -> task bar settings, and checked if the "hide taskbar in desktop/tablet mode" setting is enabled?
Should also happen within windows than that your taskbar hides, not only if you play games.
Else I'd recommand searhcing online for what you have done here as this is no windows forum, it's dedicated to Elder Scrolls Online, which is not able to hide your taskbar
Try goggle or any other search website and search for "Windows taskbar hides if game active" or similar.