[Commons-l] Need Advice on Image Permissions

[David Blomstrom]

Can someone help me understand the rules regarding the use of articles 
obtained from Wikipedia on commercial sites?

First, my websites are "nominally commercial." That is, they're 
educational websites that have been monetized, primarily by adding 
Google AdSense.

I've used many images with the permission of the owners or creators. I'm 
also familiar with the rules of public domain - no permission needed. 
But it appears that there are at least three other classes of images I 
need to understand:

1) Wikimedia Commons
2) Creative Commons
3) GNU License

My first question regards the effect of each of these on my overall 
website. I've been warned that if I use images from one or more of these 
categories on my websites, it may compromise my entire website. In other 
words, if I use an image protected by the GNU License, then the entire 
page on which that image appears may lose its copyright status, instead 
falling under the provisions of GNU?

Is this true? If so, then this post ends here, because I can't afford to 
compromise my site in that manner.

If, on the other hand, it is safe to use such images without 
surrendering ownership of an article, page or website, then exactly how 
do I cite an image's credit? Consider the photo of a mourning dove near 
the top right corner of http://en.wikipedia.org/wiki/Mourning_dove No 
sources, credits or permissions are listed at all. Only by clicking the 
image is a visitor directed to a page that lists all that information.

Can I do the same thing - place an image on my website and simply link 
it to a page with all the legalese? If so, I would probably create a 
separate web page that includes the following text associated with 
another image from that same page and link to it:

/Permission is granted to copy, distribute and/or modify this document 
<http://upload.wikimedia.org/wikipedia/commons/3/3f/Zenaida_macroura2.jpg> 
under the terms of the *GNU Free Documentation License 
<http://en.wikipedia.org/wiki/GNU_Free_Documentation_License>*, Version 
1.2 or any later version published by the Free Software Foundation 
<http://en.wikipedia.org/wiki/Free_Software_Foundation>; with no 
Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A 
copy of the license is included in the section entitled "GNU Free 
Documentation License 
<http://commons.wikimedia.org/wiki/Commons:GNU_Free_Documentation_License>".

/Furthermore, I assume I could leave the links intact. In other words, I 
could simply link "GNU Free Documentation License" to 
http://en.wikipedia.org/wiki/GNU_Free_Documentation_License - right?

I've read the rules regarding use of such images, but it's confusing. I 
need some advice and specific examples to avoid doing anything that's 
going to get me in trouble.

Thanks!