Website hangs causing server to hang

Setup:
I have a server (windows server 2012) with two webistes on two different application pools.  Both websites connect to a SQL Server 2012 database and both are ASP.Net 4.5.  Both use JQuery, VB.Net and ASP.Net.  The only major difference is website two has a membership component (have to sign in) to it where website one does not.  

Problem:
Website 1 runs without any problems.  Website two hangs consistently.  Occasionally it works but most of the time the website just 'spins' when the URL is typed into the browser.  When I look at the ISS event logs it will say something like 'A process serving application pool failed to response to a ping'.  However; trying to access website leads to the whole server going through this process:
1. Server Hard hangs (totally unresponsive--website one starts to hang as well) until the browser is stopped.
2. After browser stops, the server will go into a 'soft hang' (The cursor moves and you can  slowly navigate on server--website one starts to work again).  This will last for about 5 minutes
3. Everything on server is fine.

I suspect it is a setting that deals with ASP.net in IIS, but I'm not sure how to verify this.   I believe this because if I disable my web.config file, the website will work fine.  However, if I have this (and only this) in my web.config:

<?xml version="1.0"?>
<configuration>
  <system.web>
    <compilation debug="true" targetFramework="4.5"/>
    <httpRuntime targetFramework="4.5"/>
</configuration>

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the website starts to crash again.

Question:
How do I verify/locate (and stop) the source of the hang?  OR what are some settings I can check?

Thanks!