Thank you for getting in touch here.
> I’d like to make the Projects and Portfolio pages and the all post pages full-width on my site.
Try to apply the following CSS code through the Simple Custom CSS plugin or child theme’s style.css
> To change the “projects” title on http://www.littletownmarketing.com/portfolio
Apologies, nothing we can do because that post type is by Jetpack. I’d suggest you to go to the Jetpack support forum to seek for an assistance.
> To change the “projects” title on http://www.littletownmarketing.com/projects
From your dashboard, go to Types > Post Type > Projects > in the “Post Type name and description” box, rename the values of “Post Type name plural” and “Post Type name singular” fields.