[plt-scheme] Newbie question about PLT web application

Hello everyone,

I've started working on the basic blog application described on the
PLT Scheme Website, but I can't seem to figure out how to put the
server online.

Does the following simply launch an application on the localhost, but
not put it online?
#lang web-server/insta
  (define (start request)
   '(html
     (head (title "My Blog"))
     (body (h1 "Under construction"))))

>From what I understand there are some other steps to putting the
server online but I can't seem to get it to work. I don't have access
to port 80 so I am trying to launch it on port 8000 or 8080. Are these
ports blocked from remote users connecting to the server?
If there are other steps to putting the basic page above online could
someone provide some code I can add to it so that it works?

Would adding the following be a step in the right direction?

#lang scheme

  (require web-server/servlet)
  (provide/contract (start (request? . -> . response/c)))

..

  (require web-server/servlet-env)
  (serve/servlet start
                 #:launch-browser? #f
                 #:quit? #f
                 #:listen-ip #f
                 #:port 8000
                 #:extra-files-paths
                 (list (build-path your-path-here "htdocs"))
                 #:servlet-path
                 "/servlets/APPLICATION.ss")

Thank you in advance!