- dunno, up to 100 concurrent. I think it can easily handle 1000 or even more, because I don't see any kind of stress on server at all.
- unless your app leaks memory no restarts are needed
- usual business CRUD apps
- isapi on windows server 2003. Frankly speaking, standalone is purely for development, when deploying isapi is THE only real option. You want that security and management ISS provides, and allows combining unigui with other isapi modules (Delphi's WebBroker), html, php, node.js, etc.
- MSSQL 2008, built-in ADO