These are system processes so you cant kill/end them!
Here's some more info about them from Neuber.com:smss.exe:
This is the session manager subsystem, which is responsible for starting the user session. This process is initiated by the system thread and is responsible for various activities, including launching the Winlogon and Win32 (Csrss.exe) processes and setting system variables. After it has launched these processes, it waits for either Winlogon or Csrss to end. If this happens "normally," the system shuts down; if it happens unexpectedly, Smss.exe causes the system to stop responding (hang).
This is the user-mode portion of the Win32 subsystem (with Win32.sys being the kernel-mode portion). Csrss stands for client/server run-time subsystem and is an essential subsystem that must be running at all times. Csrss is responsible for console windows, creating and/or deleting threads, and some parts of the 16-bit virtual MS-DOS environment.winlogon.exe:
The process "winlogon.exe" runs in the background. It's a part of the Windows Login subsystem. Winlogon is necessary for user authorization and checks the Windows XP activation code.
Edited by H4CK3R, 10 February 2008 - 04:30 PM.