There is a great little program called WinPatrol that may help. You can get it from here for free.
http://www.winpatrol.com/
This lists all your start up programs, and has an INFO button which explains what each of them is.
It also has a "Delayed start" option which allows you to set a program to start after a delay so you dont get everying starting at once.
WinPatrol will also monitor your computer and alert you when anyone tries to install a new program (maybe without your knowledge) or change your internet home page and so on.
You have a chance to say NO and stop it happening before it can cause problems.
Great little program.