What are the differences between a web service and a Windows service?
My experience has mostly been with Windows services, and I have never created a web service.
Do web services behave similarly to Windows services?
Can they have scheduling, run at certain times, etc.?
When you would use a web service in place of a Windows service, and vice versa?
They're about as different as two things can be.
A Windows service is an application that runs without a user being logged into the system, usually to process some data on the machine that needs no user intervention to work with.
A Web service is a website that, when contacted, returns XML (typically) in one of several standard formats for the service consumer to process.
One can't be substituted for the other. They are fundamentally different.