Yesterday was Microsoft's Patch Tuesday, and a record number of updates were released. When you see the prompt in your System Tray (lower right corner), click on it and install the updates. Or, go to Windows Update on your Start Menu (Vista and Windows 7) and follow the prompts. Libraries with Deep Freeze Enterprise installed, be sure to leave those specific machines on overnight to get the latest updates. Check Staff machines to update manually.
Adobe just released updates for AIR, Flash for Internet Explorer and Flash for Firefox. Install when you see the prompts, or go to http://www.adobe.com/ to install manually. You'll need to visit with both IE and Firefox to get the proper plugins installed.
CCleaner updated earlier this month - download and install the update and clean out your temporary files now.
And while you're at it, why not back up your files? Getting your computer updated and protecting your stuff can be pretty satisfying!