cthelper.exe is installed with Creative Labs Soundblaster Devices. It's purpose is to aid 3rd party developers create plugins/software for the card. In this way it is a non-essential system process and can be removed from the task-bar/startup.
Non-system processes like cthelper.exe originate from software you installed on your system. Since most applications store data in your system's registry, it is likely that over time your registry suffers fragmentation and accumulates invalid entries which can affect your PC's performance. It is recommended that you check your registry to identify slowdown issues