I am having a problem with a very simple internal web application:

Windows 2000 (up to date service packs)
ASP.NET (Patched)
Microsoft SQL Server 2000 - 8.00.760 (Intel X86) Dec 17 2002 14:22:05 Copyright (c) 1988-2003 Microsoft Corporation Enterprise Edition on Windows NT 5.0 (Build 2195: Service Pack 4)

Both the web server and the database are running on the same system.

Most of the time the web app works but there is a sporadic problem where my internal user reports that the web site freezes; he hits a button and IE says "waiting for <servername>" and just doesn't come back. I've only managed to be around once while this was happening. I saw the that disc/CPU on the server were at idle levels (<5%). There was one running process in the Enterprise Manager current activity window that was waiting on a wait type of NETWORKIO. The host was listed as the same server. I wouldn't think that network traffic would be involved since the web server is just talking to the db server which are on the same machine. Of course, the user's web browser is running across the network but the web browser isn't talking directly to the database (it talks via way of the ASP.NET application).

From the user's perspecitve this app is flaky and unreliable. I'd really like to fix this but I don't know what I can do. Has anyone seen anything like this?