As for fair use issues, I think someone will come along and comment.
How did you know I'd come along and comment?
It's an interesting situation when works fall into the public domain when they may still have characters or images that are still protected by trademarks.
Fair use of trademarks is slightly different than fair use for copyright. In most cases a trademarked element can't be referred to without using the trademarked name and/or visual element!
Any use here on the site would be fair use as it's for education and informative purposes. Since the material isn't being altered, it's non-commercial and the work cannot be identified without the presence of the trademarked elements - such as names, logos, visual elements, etc.
Any "transformative" use of material in a similar no copyright/trademarked element may go beyond "fair use" and get into trademark violation.
Take the public domain cartoons on DVD/VHS - Warner Brothers, Popeye, Superman, Betty Boop - all have active trademarks - but these DVD feature unaltered works and present the works as they were originally presented. It's only when they use images on packaging not taken from, or not directly based on the material presented where it crosses into trademark infringement. They can't use the Superman logo on the box, but they can use the word Superman on the package in a way that identifies the contents without infringing.
I suggest to anyone doing anything of a commercial for-profit nature with public domain material that may have trademarked elements, to consult a lawyer - to make sure when it comes to trademarks, use of public domain material with the trademarked elements is presented within the bounds of fair use.
Here's a disclaimer from a favorite book of mine on American Gas-Station History - It is recognized that some words, model names and designations, for example, mentioned or featured on or in this book may still be the property of the original trademark holder. They are used solely for identification, illustrative and informational purposes under the "Fair use provisions." of United States Code Title 17