1) Which is better to use http://www.site.com or site.com?
2) Which is better / or /index.php
3) Is it better to put content in it's own directory or site.com/article.php?
4) Is there anyway to SEO images?

Thanks!

It doesn't really matters which one you use. But search engines treat http://www.site.com different to site.com, i.e. two different domains. So it's best to use one, whichever you decide to, but make sure the same is used all over.

Again, it's not much of a matter, but use one of them since they may be (by few search engines), considered as duplicates.

Directories provide additional keywords for the url. For example:

domain.com/articles/make-php-run-fast.html

Is better than:

domain.com/make-php-run-fast.html

Although that only has a slight effect.

If you're talking about your images getting indexed in Google Image search, then you can use descriptive file names such as Rotana_Beach_View_Beautiful.jpg instead of rotana001.jpg .. Or if you're talking about optimizing your image gallery pages, then surely you can use descriptive titles, descriptive file names, and a reasonable description (text snippet in the html) for the image. Such as "The rotana beach was looking amazing in the sunset."

Hope that helps

I think it is better to use www since this is somehow standard and people use it and remember websites this way. Just make sure you redirect in your .htaccess from non www to www. Check code below

It doesn't really matters because when users link to your site, then don't really type it by hand, they rather copy/paste the url they found interesting. So as long as the urls on the site are consistent throughout, it won't really matter.