“So what you are saying is that it would be better to create each review as a different html-file, rather than having one review.php?id=1919 that generates each review based on the ID?”
You can do this in php, dynamically generating a different url for each page. If you don’t know php all that well you’re better off using a cms or blog engine such as Joomla, WordPress etc. You can set them up to display search engine friendly urls for your pages.
About the php-include which is also serverbased, if you open the .php file in notepad it will say something like but on serverside it enters the whole code for 123.php. Will this have an affect on google too?
All google will see is the Html that is generated by your php code. All you need to concern yourself with is how the URL’s look for each dynamically generated page.
Excuse my bad english, i’m unfortunately from Sweden
Your English seems pretty good to me.