Very simple, Windows provides you with the tool.
Control Panel > Admin Tools > Services then look at the top left there is an "export list" button provided, you can save your services list anywher you wish, see screeny attached.
Would also add that if you want advice/knowledge on Services ( or anything else about Windows) then take a trip to Black Viper's site and look at the guides there >>
http://www.blackviper.com/ <<
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