You can't run a Progress Database as a Windows service - but, the Admin Service is a Windows service. If you configure the databases in Admin Service you can configure them with auto-start and when you configure the Admin Service in the Windows service manager with auto-start then when you boot the machine the databases will start automatically - if that is what you want.
Other than that I vaguely remember about something like AutoExNT ...
Heavy Regards, RealHeavyDude.