Process Explorer
http://www.sysinternals.com/Utilities/ProcessExplorer.html
Process Explorer, by Sysinternals is a very powerful version of task manager. It shows you the command line used to open your running processes, which files they have open, and which processes spawned them.
Process Explorer allows you to kill process trees instead of killing one process at a time. It’s ability to kill processes seems much stronger than the standard windows task manager, and with the extra information you get, Process Explorer can be very useful.
The program is small and runs fine off of a CD.