Need first post to stay the same

You could either hand code it into place. Or you could use something like Adhesive to stick it there.

search for Adhesive or Sticky

If you’re running WP1.5, you’ll need the latest release of Adhesive. You can find it here:

https://www.asymptomatic.net/wp-hacks

Why not just use CSS to code a box that appears before the posts ? And you then put your text inside that ?

Then set posts on first to a low number maybe zero or one in admin. Or have a bunch and use more. All the tools are in there. We just need to think creatively about using them. You could set up a front page only cat.