I had this problem earlier today—here is the fix:
8.1. Accessing Properties in the Internet Services Manager Causes the Internet Services Manager to Crash
Viewing any Web sites, the Default Web Site, Virtual Directories or sub-directories may cause Internet Information Server (IIS) to crash. This problem is caused by a corrupted registry key. To resolve the problem, you can modify the registry key values using the registry editor (regedit.exe). Steps to reproduce: 1. Start->run->inetmgr 2. Select a virtual directory and attempt to modify its properties.
To resolve this issue:
1. Open the registry editor by selecting Run from the Start menu, typing regedit, clicking OK.
2. Navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\ASP.NET and locate the registry key with the name 2.0.40301.9 (pd4.040301-0900).
3. Rename this registry key to 2.0.40301.9.
4. Select the registry key named 2.0.40301.9 and locate the sub-key named DllFullPath.
5. Right-click the sub-key named DllFullPath and select Modify.
6. In the Value data: text box, type the file location of the aspnet_isapi.dll for the .NET Framework version 2.0.40301.
For example, C:\WINDOWS\Microsoft.Net\Framework\v.2.0.40301\aspnet.isapi.dll. Note Windows may not be installed in the C:\WINDOWS directory on your server. Be sure to use the proper path to the Windows installation for your server.
7. Select the registry key named 2.0.40301.9 and locate the sub-key named Path.
8. Right-click the sub-key named Path and select Modify.
9. In the Value data: text box, type the folder location of the aspnet_isapi.dll for the .NET Framework version 2.0.40301.
For example, C:\WINDOWS\Microsoft.Net\Framework\v.2.0.40301. Note Windows may not be installed in the C:\WINDOWS directory on your server. Be sure to use the proper path to the Windows installation for your server.
10. Close the registry editor.
Source: http://msdn.microsoft.com/vs2005/currentreadme/default.aspx
Hope that helps someone. Thanks to Daniele Bochicchio for pointing this out to me. --Marcie