problem with windows update... help please!

i've recently installed vista ultimate 32bit on a brand new PC (homebuilt) and windows update constantly, randomly crashes. The info on the error i get is below:

Log Name: Application
Source: Application Error
Date: 12/08/2008 7:27:22 PM
Event ID: 1000
Task Category: (100)
Level: Error
Keywords: Classic
User: N/A
Computer: ChiChi-PC
Description:
Faulting application svchost.exe_wuauserv, version 6.0.6001.18000, time stamp 0x47918b89, faulting module ntdll.dll, version 6.0.6001.18000, time stamp 0x4791a7a6, exception code 0xc0000374, fault offset 0x000b015d, process id 0xd00, application start time 0x01c8fc5d9d8182fa.
Event Xml:
<Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">
<System>
<Provider Name="Application Error" />
<EventID Qualifiers="0">1000</EventID>
<Level>2</Level>
<Task>100</Task>
<Keywords>0x80000000000000</Keywords>
<TimeCreated SystemTime="2008-08-12T09:27:22.000Z" />
<EventRecordID>2398</EventRecordID>
<Channel>Application</Channel>
<Computer>ChiChi-PC</Computer>
<Security />
</System>
<EventData>
<Data>svchost.exe_wuauserv</Data>
<Data>6.0.6001.18000</Data>
<Data>47918b89</Data>
<Data>ntdll.dll</Data>
<Data>6.0.6001.18000</Data>
<Data>4791a7a6</Data>
<Data>c0000374</Data>
<Data>000b015d</Data>
<Data>d00</Data>
<Data>01c8fc5d9d8182fa</Data>
</EventData>
</Event>


Basically, it causes Windows update not to work, sets my theme to windows classic and drives me absolutely insane by popping up completely randomly.

Can anybody help? (It seems Microsoft cant))

thanks... i reinstalled vista without any dramas. i then installed all the programs and add-ons i thought were causing the problem (one by one to determine the fault)... nothing. its working fine. i havent installed any of the windows updates because i think it might be one of them. is my thinking justified? if so what should i do?