Separate the Start host from Explorer
**StartMenuExperienceHost** is its own process. If the whole taskbar is unresponsive, **explorer.exe** hung; if only Start is dead, the host package is the suspect.
Get-Process explorer,StartMenuExperienceHost,ShellExperienceHost -ErrorAction SilentlyContinue | Select-Object Id,ProcessName,StartTime
Stop-Process -Name explorer -Force