Here are several possibilities that I have used:
1) Use the example Hello World portlet from http://www.jboss.org/portletswap/portlets_tutorial.html. All of your static text would appear in the portlet source.
2) Use the Hello World JSP portlet (available at the same location). Now you can place your HTML text in a JSP.
3) Use the JSP example portlet that comes with JBoss Portal. Then you can either edit the JSP file at jboss-portal.sar/samples/portal-jsp-samples.war/WEB-INF/jsp/view.jsp.
4) Place your HTML into CMS, and plagiarize (I mean "re-use") the CMS Portlet source code to create your own variation of the portlet and let it display the HTML text.