MSConfig
MSConfig is a utility that can help us determine what programs are starting up when we turn on our computers. It allows us to choose the programs that are starting, without having to uninstall them. This can be very helpful if our computer is slow to start or we cannot get to the Internet.
To start MSConfig, click on the Start button and click on Run. Type in msconfig and click OK. After a few seconds, the System Configuration Utility will appear. Click on the Startup Tab and the screen should look something like this:

Any program that is checked will run when our computer starts. By unchecking the programs we can prevent them from running at startup. After checking out what each program does (through answersthatwork.com or Pacman's Portal) we can decide if we want to uncheck it.
After unchecking the programs that we don't want to run at startup, when we click OK the computer will prompt to restart. This is necessary - after all, these programs are already running! When our computer starts up again, there will be a message like this:

Check the Don't show this message box, click OK, and we are done.
One thing to keep in mind: msconfig will stop programs from running at startup but it will not keep them from starting while our computer is running. It is very possible that the program(s) will start up while we are doing other things. There can be any number of hidden 'trigger' programs that look to see if one of our unchecked programs is running, and start it up if it is not! The best way to deal with programs that we do not want running on our computer is to uninstall them.