We have a few fixes for you on how to deal with stuttering, freezing, and FPS drop issues with Elder Scrolls Online.
The launcher stays on while the game runs. You have to shut it down manually.
You can disable core parking, a sleep state that runs in x86 processors, and is de rigeur for modern versions of Windows. To accomplish this, we suggest you download and use ParkControl. You can also use Windows’ own Powercfg.exe utility to modify further power settings and you can go into Windows’ Power Options to make parking options show up in that screen. This all assumes you are administrator of your computer. You can get the programs with instructions here.
Lastly, you can modify settings so that the eso.exe process is set to high. This is a simple matter of entering Windows Task Manager. You can rich click on the Taskbar to see the Task Manager option, or press the Ctrl, Shift, and Esc keys together and choose it from the menu there.
After that, you go to Processes, find eso.exe, right click it, choose Set Priority, and finally, change that to high. Now, a fan has warned that setting the file high priority might cause problems, so caveat emptor.