Question on IIS Application Settings

[LiLo]

Hi,

 

I would like to use IIS to host one asp.net website. The website will be used by many users simultaneously. I have 3 doubts to ask:

 

Does IIS allocate resources to these users one after another or does IIS use multi threads to process these users at the same time?

 

Also, regarding application settings, IIS 5.0 has Low, Medium, High. Does IIS 6.0 have any improvements over those of version 5.0?

 

Also, are the application settings related to multi threading?

 

:)