You have to start by deciding between html and php.
HTML is easiest in the short term: essentially you just scrape yourself (ouch!) and then the resulting raw html becomes your new pages. PHP is necessary if there are dynamic parts of your site: things that will be changing without your hands-on involvement.
If you don't already speak php, and you need to change the site right away, you can always put it into html for now, and then change it later. Or, ahem, slither into it sideways by moving from plain html to ssi's to php includes* to complete php pages.
:: pause here for someone else to insert plug for extensionless URL so user doesn't see the difference ::
* Pause here to ask the heavens where the blasted variable got to, if it's neither local nor global, because it can't just disappear can it?