Office System (2003) SP1 Patches
You should consider installing SP2
Office System 2003 Service Pack 2 was released in the end of September 2005. You can download SP2 for Office System 2003 right here:
Download Office System 2003 SP2 – Client only (50.5mb)
Download Office System 2003 SP2 – Full administrative installation (101mb)
For detailed instructions on how to integrate SP1 into your Office 2003 products see the following articles: Front Page 2003 SP2 Slipstreaming, Office System (2003) SP2 Slipstreaming and One Note 2003 SP2 Slipstreaming.
Required Patches
Office System (2003) + SP1 requires the following patches:
April 2005
MS05-023 : Vulnerabilities in Microsoft Word May Lead to Remote Code Execution (890169)
February 2005
MS05-012 : Vulnerability in OLE and COM Could Allow Remote Code Execution (873333)
Office Update
You should also go to the Office Product Update page for a full system scan that will tell you what you need and what you should download to keep your Office Suit up-to-date.