Here's how I did it. I wanted "Task" to be my default entry type. Found at
http://support.microsoft.com/kb/180139 how to add new entry types to the Journal. (Requires editing the Registry and the article is written for OL2002 but still worked for me using OL2007) I've also found out through various web searches that "Phone call" is hard coded as the default entry type so DON'T delete it as it may cause your computer to blow up. Lawyers must have gotten to programmers to get that set up cause they are one of the few I know of that bill for phone calls.
So, instead of adding (or subtracting) an entry type I renamed "Phone call" to "Task" and renamed "Task" to "Phone call" by right clicking on those items under the Journaling list and selecting "Rename".
So far it works. Computer has not blown a gasket. When I right click on the Journal screen the default entry that it jumps to now is Task.