include gallery in a php coded website? How to do?

It's a pitty that i have to start a new topic, but i searched this forum and i'm not suceeded to integrate gallery in my own php coded website.

I have a website with an index page where i include the other pages, style:
http://www.domain.com/index.php?Section=gallery

So every page is included in my index page.
I played with the html wrapper and that works fine, but i want to include it.
It is looking nice, but when i click on the album link i go to http://www.domain.com/gallery/albums.php in a new page
I want that it stays in the include layout. I read that it is better wit a include footer and header and have every section an own page, but i'm allready too far with this site, to chance.

So who can help me with this?

The site is http://www.puurajan.be/index.php?section=gallery

If you click on album it open's in a new page, that's the problem.

thanks in advance

best regards,

Wim