http://www.pacs-portal.co.uk/startup_content.php

This link is to a page describing how to see what is running on your pc and how to disable programs from running automatically at startup. This is important information for any pc user. There are links to copies of msconfig, other startup utility pages as well as a zipped list of programs that try to insert themselves into the start up processing and whether you need them or not. This page deals primarily with start up issues and their list is not comprehensive wrt all tasks running on your pc. He does have a nice list of related links to general pc maintenance issues.

The following two links address all running tasks with the ability to search a regularly updated list of known tasks and what they are and do you need them or not.

Answers That Work task list -

http://www.answersthatwork.com/Tasklist_pages/tasklist.htm

LIUtilities Task List -

http://www.liutilities.com/products/wintaskspro/processlibrary/