IIS runs in 2 modes (application isolation modes):
1. worker process isolation mode is a new feature of IIS 6.0.
2. IIS5.0 isolation mode - for compatibility with apps depending on IIS 5.0

To determine where your IIS log files are stored, please execute the steps below on your server:
1.       Go to Start -> run
2.       type inetmgr
3.       Find your web site under the tree on the left and right-click on it.
4.       Choose properties
5.       On the Web Site tab, you should see an option near the bottom that says "Active Log Format."  Next   
         to it is a Properties button.  Click on the Properties button.
6.       At the bottom of the General Properties tab, you'll see a box that contains the log file directory and
the log file name.  The full log path is comprised of the log file directory plus the first part of the log file name. 

For example, take the following case.
1.       Log file directory: C:\Windows\System32\LogFiles
2.       Log file name: W3SVC1\exyymmdd.log
3.       Your full log path to put into SmarterStats would be: C:\Windows\System32\LogFiles\W3SVC1

Anonymous access
Basic
Digest
Windows
MS .Net Passport

The advantages of upgrading the server that hosts your existing IIS Web sites and applications to IIS 6.0 include the following: . Reduces the time required to deploy IIS 6.0. Upgrading requires minimal user
interaction. . Reduces possible configuration errors. Because the majority of the current
operating system, IIS, and Web site configuration settings are retained during
upgrade, fewer configuration errors result. The disadvantages of upgrading the server that hosts your existing IIS Web sites
and applications to IIS 6.0 include the following: . Retains previous versions of software. The upgrade process upgrades only
software components identified by Microsoft® Windows® Server 2003, Standard
Edition; Windows® Server 2003, Enterprise Edition; and Windows® Server 2003, Web Edition. Any other installed software components, such as applications or
application dynamic-link libraries (DLLs), remain unchanged. . Retains the previous registry configuration. The upgrade process makes the
appropriate modifications to the registry entries identified by Windows
Server 2003. Registry entries are created by an application as it is installed,
but are not removed when the application is removed. Cumulatively,these registry
entries consume disk storage and can make troubleshooting registry-related
problems more difficult because the unused registry entries can have similar
naming conventions to active registry entries.

IIS metabase is an xml file the contains all the  configutations

In IIS 5.0 logfile formats are 3 types 1. w3c extended logfile format 2. NCSA Comman logfile format 3. ODBC loging In IIS 6.0 logfile formats are is 4 types 1. w3c extended logfile format 2. Microsoft IIS logfile format 3. NCSA Comman logfile format 4. ODBC loging