Go to the start menu then to run and type in msconfig. Go to the tab Sevices and click the box "Hide All Microsoft Services" then uncheck anything that you dont want to run when you computer starts up. Generally if you dont know what it is then uncheck it.
Next go to tab Startup:
and uncheck anything there that you dont want running. Then restart.
If you dont want to do all that tinkering which isnt alot, then download Spybot Search and Destroy and go into the advanced mode click tools and system startup. It should be more informative on helping you choose what to have running and what to not.
Yo can use that same program for kiling processeses like you do with the task manager. But spybot usily is more forceful with kiling processes so you may want to proceed with a little caution.
Hope that fixes your problem.
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