you could remove all of them, but it's better to disable
the startup from within the programs. Most Programs give
you an option in the preferences to load on startup or not.
2nd...go to start/programs and delete the entry's in the
Autostart pop-out if any.
If you don't want to edit the registry manually, your best option is to uncheck the items from the Startup listings and download the script from Kelly's site which clears the disabled items from the Startup lists.