To find out more information about a specific service, you can double click it to bring up its properties window.

As you can see, there are four tabs here. The 'general' tab gives you essential information about the service, including its actual name according to the system (this will be important later), the 'path to executable' which shows the .EXE file that Windows uses to start the service, its startup type and status.

The 'log on' tab allows you to change what account the service uses to perform its function. Just like every other user and application on a Windows XP box, services need an account (which defines what security restrictions are in place) to run.