Two days ago, we recommended that you get the latest Microsoft patches and to visit www.windowsupdate.com.
But nowadays it really makes more sense to recommend Microsoft Update instead of Windows Update. Microsoft Update does everything Windows Update does plus, in addition to patching the operating system, it also patches other common Microsoft software. This includes patching software like Word, Excel, SQL Server etc. In fact, many people probably thought Windows Update did this already!
Patching Word is quite important - we're regularly seeing targeted attacks made by e-mailing booby-trapped DOC files to companies. Word isn't often patched as well as Windows itself is, and DOCs go through gateway filters much more easily than EXEs do.