Hi I would like to know how you can change the language of news: posted
by, categories, or remove it entirely .....

thanks for any replies

I'm not entirely sure what you mean. If you mean change the language of news articles that you've already posted, the system can't do that. What you would need to do would be manually create a duplicate article for each existing article with the language translated to your desired language, then assign it to a category. You can then display only news articles assigned to that category using the $cat[] variable, see here

http://code.google.com/p/n-13news/wiki/Integration