Make use of a
<pre> tag it will work.
Inside your blog try "&lifier lt" (without space) to create < and "&lifier gt" (without space) to create > inside your Web Coding.
This syntax can be used to create "<" and ">" symbols on some web site. Otherwise it'll treat your code included in the blog article and can show its output.
You should use
Also Joomla includes a native wordpress plugin to show code and syntax highlighting, in line with the Geshi project.
It's not hard to use, just make sure it's enabled inside your plug ins config:
<pre lang="html" > <p> some text </p> </pre >
Hope it will help!
Make use of the a jQuery highlighter.