In an attempt of blocking a viral service on my system (which was restarting my system automatically for every 30 seconds), I disabled all the services, and later enabled trustworthy services only.

(note: Hide all microsoft services didn't work blocking the auto restart so I disabled all services)

Now I have been succeeded in blocking automatic restart and I am able to access internet and all other necessary stuffs. Well, however system audio is mute(definitely because a necessary service is not running). Now I need a list of services that need to be started (set automatic) on windows 7.