Having (sincerely) said you should read Oremus's story, I'm now going to quote the immediate news-you-can-use part of it, where he explains how to disable Java for the main browers.

To view our interactive tools properly, you need to be using a Java-enabled browser (Microsoft Internet Explorer v. 3 or above, or Netscape v. 3 or above), preferably on a Windows 95 and higher ...

Next week’s Patch Tuesday updates for Windows will include a monumental security fix. An update to Internet Explorer, for installation on PCs running Windows 7 Service Pack 1 or Windows 8.x ...

To help users defend themselves against Web-based attacks using Java plug-ins in the browser, Microsoft’s FixIt tool will block all of the Web-based vectors for attack on all versions of Java ...