Those are user defined terms, so they can mean whatever you want them to....the usage and terms will vary from company to company.
My guesses would be:
Utility macro's are likely a touch more generic, e.g add commas between macro variable lists, or retrieve information on a specific file
Standard macros, would be macros that you use to do accomplish some sort of requirements but is usually more complex and has multiple steps, e.g A reporting macro to prepare financial end of month statements.
And someone else can interpret those entirely differently.