If you want to use the WordPress Posts Content Source to add pages to your SlideDeck, but want to include/exclude certain pages then you'll have to add custom taxonomies to your pages.
By default WordPress Posts have tags and categories, but Pages do not. The easiest way to mark certain pages on your WordPress site for inclusion in a SlideDeck is to give them categories or tags. A plugin like GD Custom Posts And Taxonomies Tools allows you to add custom taxonomies to your posts and pages.
For instance, you could add a category called "Home Page SlideDeck" to your pages and then those pages can be pulled into your SlideDeck.