Simple commands to create a full dump file (needed to analyze .Net processes) of the IIS process.
On Vista and later it is possible to right-click the process in Task Manager and select "Create Dump File".
Remarks
To create a dump for a IIS running in 32 bit mode on a 64 bit machine you have to use a 32 bit version of ADPlus to generate the dump.
However, having the Debugging Tools for Windows installed one can not only create hang dumps (snapshot of the process' memory at a given moment) but also crash dumps, that is, when a process crashes. In a crash dump there will be an active exception on one of the threads making it easier to debug the exception since the stack may be walked and parameters printed.
<Path to WinDBG>\adplus.vbs -hang -pn w3wp.exe -o c:\temp
Where
-hang = create a hang dump, a snapshot of memory just in time.
-pn = process name
-o = out directory
-crash = creates a crash dump, waits for the process to crash and creates a snapshot of the process as it was when it crashed.
Don't forgot to download the machines mscordacwks.dll