While Blackviper does tell you the default processes you can disable from Windows 7 it does not include anything you've installed since then that starts automatically. The best way is to follow his guide loosely and also Google anything you are unsure of. I have mine down to about ~40 on start-up but I run a high load due to I use my system for everything (far too lazy to use a separate gaming and everyday partition). It's about ~680Mb Page File on start-up and 0-2% CPU usage.
The best way to shut things off is open Start Menu and type "Services" and hit <Enter> and select "Services (Local)" from the left list pane and read the description and disable anything you don't need (right click on something and hit Properties then change the "Startup type").
As a guide, these are services I have set to Automatic set-up and Disabled and a small portion of the Manual. If it's not on that list you can turn it to Manual or Disabled and the computer will run, but a program may stop working depending on what all you use. Always use lists such as these and BlackViper as guidelines, not definite rules.
You want SuperFetch off, it is a resource hog that does nothing to help you
