1. it is possible with wininet
2. wininet is a low level api used by IE and the like. Msinet is a higher level ocx.
3. Running a service sing VB is not a good idea VB was never designed to do it. Altough there is some Code in MSDN for a C++ ocx which allows VB to interact with the service control manager.
Writing an FTP service with VB is going to be a lot of work when there are plenty of cheap FTP servers commercially available. Is there any particular reason whic you want to write your own.