I have this code to display all post:
Shows the two types of post but does not work pagination. When I go to the next page shows the same post in the home page. I do not know what the problem is.
And in the post_type “articles” category are not displayed.
Try adding pagination parameters to your query:
More on pagination parameters here: http://codex.wordpress.org/Class_Reference/WP_Query#Pagination_Parameters