There may be two separate issues here. One, your iis  may be failing due to a
duplicate port number(s) - check the port numbers against all the Web sites
hosted on the server's IIS, i.e. are there any Web sites with a status of
'stopped' or are failing to start on server  reboot or iisreset?.
Two, I've seen the 'write protected memory issue' problem where I'd previously
added an additional Web front-end server to my farm and enabled/disabled Office
search on that new Web front-end server. The errors showed up in the main
(original) Web front-end server (the one running  Central Admin). Have you
recently extended the farm and/or enabled any additional services? Have you also
tried rebooting the SQL server (assuming the SQL server is on a separate
machine)?

I've resolved the same problem with this hot fix
support.microsoft.com/default.aspx/kb/923028

I am glad someone else is seeing this as well. We have 3
wfes,1 app server, and an active/passive sql cluster. And yes, we
see the exact same thing. For the most part the servers seem to
still respond fine but you can not do anything with IIS manager  or
directly with the services. The only answer we have found is reboot.
BTW, when this non-responsive condition occurs, it does on multiple
machines.

For the write protected memory issue. We have a theory on it that we
discovered trying to implement the symantech sharepoint  backup
solution. We found that the VSS writers were hanging causing the
backups to fail. MS very recently released a OS patch the fix the
vss writer error(dont know the actual number) and it has appreared to
fix the bad memory error message.

This looks mysteriously like the notorious SPTimer Memory leak problem

That could be likely. We do have a memory leak issue as well and I have not
reserached it yet, so I will start here. The link refers to restarting the
timer service....does this have to be done frequently? I am assuming this
is not a one time fix?

You can get a free tool to reset SPTimer on all WFEs using an STSADM
command from the Mindsharp Premium Content page.

This does not seem to have resolved the issue, any other thoughts?

Have you installed .NET 2.0 SP1?
www.microsoft.com/.../details.aspx
AD3-AACF-A7633F706BA5

There is an issue with programs such as Anti-virus locking IIS that is
included in SP1. If you cannot load SP1, then I would at least try the
patch support.microsoft.com/default.aspx

There is an outside chance the above is your issue. It is always
possible you have a corrupt metabase. In that scenario, you will have to
1. Restore from a metabase-only backup (don't restore the system state
as it will overwrite the registry, etc.). If you aren't doing standalone
metabase backups (best practice with SharePoint server  2007, btw... see
here mindsharpblogs.com/.../3486.aspx )

Then you could 1. Stop the Windows SharePoint Services Web Application
service in Central Administration for the WFE server in question. 2.
Uninstall IIS on that WFE Server 3. Reboot and re-install IIS on the WFE
Server 4. Start the Windows SharePoint Services Web Application in
Central Administration for the same WFE Server in question. But, be sure
to backup/document everything in the inetpub directories, multiple host
headers, assigned IP addresses, and SSL Certificates. These are not
copied back to the WFE Server from the configDB.