Uncy, basically what you have to do is double click on the entry in the services console and change the 'start-up type' to 'manual' (from the drop down list). Don't change it to 'disabled' or you won't be able to use the application at all.
You will find that stuff such as Ad-aware will add itself to start-up, even though you might only use it weekly... so just keep an eye out. There's much more in the
Windows Tweak Guide about what is essential, what you can disable, etc from start-up.