TimeBroker service is responsible for background activity of StartScreen Apps.
"If this service is stopped or disabled, then background work might not be triggered."
It is possible that after disabling it, all Active Tiles won't work anymore.
I had the same problem, StartScreen hangs and not responding.
In my case it was a TimeApp, 3rd party ClockApp it was trying to connect to a server or something and an till it could StartScreen was not usable.
I've resolved it by disabling in PC-Settings TimeApp permissions to work in background.
StartScreen worked since then flawless, but to be sure I've uninstalled whole 3'rd party TimeApp from StartScreen.
Now I have no problems any more, TimeBroker service is working fine and other active tiles work as well.
Best wishes for the New Year.
Piotr