Services are programs that start up when your computer boots. They continue to run in the background while your PC is on, some services load automatically, some when a program is used. Some of these services are not needed by various users and can be safely disabled. But remember, there are some services that must not be disabled.
To disable any services, click on the Start button, type in 'services.msc' and press OK. You can single-click on any service to see a description of what that service does. If you do not need that service, right-click on it and select 'Properties'. In the 'Startup Type' drop-down box you can choose 'Automatic' (automatically starts up when you boot your system), 'Manual' (lets Windows decide when and if to start the service), or 'Disabled' (Will not load the service at all). After making your selections, close the window and reboot your computer for the changes to take effect.