Your computer won't survive on the Internet unless you keep Windows, Internet Explorer (even if you don't use it), any other browser, other software like Word, Acrobat, etc., and your firewall, antivirus, antispyware, etc. up to date. Note: new computers always come with old software. Count on it. [survey says...]
The new "Microsoft Update" does everything that Windows Update does and more. In addition to updating Windows, it also patches other common Microsoft software, like Microsoft Word, Excel, etc. It's time to make the switch. Microsoft Update requires Internet Explorer.
http://update.microsoft.com/microsoftupdate/
http://cybercoyote.org/url/182.html -- instructions
Sometimes updates or upgrades just don't work out. It's best to back up your system, or at least your documents before you update. What would you do if you ended up with a computer that won't start?
Update: Secunia now offers a [free] "Personal Software Inspector" (PSI). Use it to scan all the installed applications on your PC to find out which programs have important updates or are missing security patches. It is very thorough and gives you great info to help you find the updates that you need. You do need to download and install the Secunia PSI, but it's well worth the trouble. [Secunia Forum]
CNET'S TechTracker is similar to Secunia's Personal Software Inspector. TechTracker shows you the software that is out of date and provides you with the information to decide which updates you need. [more alternatives]
SANS Institute has very comprehensive information on security threats and solutions, including updates and patches.
Microsoft (or any other sensible organization) never distributes software updates via e-mail. Always go directly to their Web site to get the updates. If you get a message that purports to be a security update from Microsoft it is bogus. Just delete it!
Microsoft does deliver update notices for Windows, Internet Explorer, Outlook Express and other programs. You can sign up for these (technical) notices with just your email address. ["How to Tell If a Microsoft Security-Related Message Is Genuine"]
Microsoft provides lots of update information at their new security site. Also, follow the links at that page to "Security Updates" and then (probably at the next page) to "E-mail Updates".
The SANS Institute has very comprehensive information on security threats and solutions, including updates and patches.