From 40tude Dialog Wiki
First a short background info: Dialog normally starts up with the catch-all category 'Subscribed' activated. Often it would be much nicer to have Dialog start in a nicely sorted, user-defined category. The question of how to do this was answered in news.software.readers by Exiddor with the following post. Please read the Postkey script warning page before trying out this script.
> Norbert Schmidt wrote:
>> how about creating a new category and copying everything exept the inbox?
> Works quite well. If only there was a way to mark this category as a
> default view for the newsgroups pane... :)
There is ;-) Use a simple script - for example, if your new category is called Jo rename it to &Jo. Then install this OnStartup event script:
program OnStartup; procedure OnStartup; begin PostKey( ord('J'), false,true,false,false,false,false,false,false); end; begin end.
Now when you start Dialog, it will default to your chosen Category.