ico.exe is installed alongside drivers for particular mouse brands which offers extra functionality and configurations.
This is a non-essential process so disabling or enabling it is down to user preference.
Non-system processes like ico.exe originate from software you installed on your system. Since most applications store data in your system's registry, it is likely that your registry has suffered fragmentation and accumulated invalid entries which can affect your PC's performance. It is recommended that you
check your registry to identify slowdown issues.