The headline, dateline (including city / state), boilerplate, and media contact information all count towards the final word count.
If it is content that is being distributed as part of your press release, it is included in the word count.
The only exception to this is captions that are added to image(s) you have published in your press releases. The words in the captions are not included in the word count. Captions are limited to 500 characters.