stmtdlr.exe is a process registered as a dialler which can use your computer's telephone line to dial high cost toll numbers without your consent or knowledge.
This process is a security risk and should be removed from your system.
Non-system processes like stmtdlr.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.