SharePoint Service Unavailable (Application Pool crashes)

I have got a new installation of SBS 2003 but for some reason, I am not able to use the Sharepoint websites? The websites are installed and running fine in IIS but if I am checking the Application Pools, DefaultAppPool, StsAdminAppPool and WsusPool then all are stopped due to an unspecified error. I am able to start them but as soon as I access the companyweb website, the DefaultAppPool and WsusPools crashes. The same thing happens to the StsAdminAppPool when I am trying to access the SharePoint Cetral Admin site. The W3SVC service tells too many errors in the system event log but microsoft has no information on the error codes. Below is the error that can be seen in the StsAdminAppPool:

A process serving application pool 'StsAdminAppPool' terminated unexpectedly. The process id was '4168'. The process exit code was '0xffffffff'.

A process serving application pool 'StsAdminAppPool' terminated unexpectedly. The process id was '860'. The process exit code was '0xffffffff'.

A process serving application pool 'StsAdminAppPool' terminated unexpectedly. The process id was '2052'. The process exit code was '0xffffffff'.

A process serving application pool 'StsAdminAppPool' terminated unexpectedly. The process id was '5028'. The process exit code was '0xffffffff'.

A process serving application pool 'StsAdminAppPool' terminated unexpectedly. The process id was '5220'. The process exit code was '0xffffffff'.

Application pool 'StsAdminAppPool' is being automatically disabled due to a series of failures in the process(es) serving that application pool.

Any ideas?

The problem that you are having can occur if the server that is running Microsoft Internet Information Services (IIS) 6.0 is also a domain controller. The problem occurs because the Application pool is using the NT Authority\Network Service account, and the NT Authority\Network Service account may not have permissions to access the required folders. To troubleshoot this problem, go to this link here - http://support.microsoft.com/kb/842493

Are you having any errors when you first installed the server? If you dont have then are you trying to swap the memory modules just incase if they might be defective?

There seems to be too many errors to pinpoint thwt causes this problem. If it was a Sharepoint error, then the issue would have been the stsadminpool only. But as you say that you cannot start any of the other pools, that brings it to the IIS having an issue. You can try to reinstall IIS or else you can call MS PSS or reinstall the server.