Balraj at DigitalGrabber extols the virtues of a program called Startup Control Panel, which'll help you clean up your Windows startup. I just downloaded the standalone exe file to give it a try, & it really is a decent interface for the reg entries that need attention for this task.

"There are, however, many programs that do not give you the choice and no matter how many times you remove them, they return. Two that I find really annoying are the "Windows Messenger" and the "Quicktime Task". Both sit in the system tray and I don't need or want them there."