Ah, I see. Well as long as the site reflects you/your art in some way, that's fine.
As for iframes, they've fallen out of favor in the last few years because they're not very user-friendly. People who want to bookmark a specific section in your site won't be able to because they can only bookmark the container frame; also, given the number of people who have popup blockers these days (or just plain don't like popup windows), having a site that relies on popups to display content can be iffy.
If you're willing to learn a wee bit of code (or at least learn enough to know where to paste the code snippet), a more accessible option would be to use a php case/switch statement. It serves the same purpose as an iframe, but also enables the user to bookmark that specific page in your site.
http://www.digital-web.com/articles/easypeasy_php/
If you wanted to get really fancy (or at least make your life much easier) you could use PHP to split your site into independent files (header, content, footer). That way when you need to make a change to one portion of the page you'll only have to do so once, rather than changing it on every single page of your site.
http://buildinternet.com/2009/12/usi...mplate-faster/
As for your gallery, take a peek at some of these options and see if there aren't any that appeal to you. The benefit to these is that while there are many users who disable popups, there are few people who disable Javascript. And all of these come with install instructions.
http://www.1stwebdesigner.com/resour...box-solutions/
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