I have full logging ( using log4net) throughout the application.
What are the key WMI variables etc that should be monitored.
If you had to pick 10 things that you would look at everyday what would they be and why are they important.
This question has already been asked, see http://stackoverflow.com/questions/603354/what-are-the-best-perfmon-counters-for-an-asp-net-application.
The answer points to this TechNet article for IIS6.0.
You can also see the description of IIS performance counters (as of .Net 4.0) here: Performance Counters for ASP.NET
You will also find lots of great information in these Microsoft blog posts: