Without seeing your intended mural, and the "similar backgrounds" to those in copyrighted movies with copyrighted images and trademarked characters, it's difficult to know if your tended murals would infringe.
Very, very, generally, from a copyright point of view, your images can't be "substantially similar" to any images copyrighted by anyone else.
Likewise, your use of a character can't confuse any consumer about whether your vacation rental is endorsed by or affiliated with the anyone else's trademarked characters, logos, or brands that signify any goods or services.
For the same reasons, if you're planning on advertising these theme murals when you market your vacation rentals, you have to be very careful about infriinging their trademarks by confusing a consumer about whether your vacation rentals or endorsed by or affiliated with the goods or services trademarked by others.
See an IP lawyer for help.
Disclaimer: Please note that this answer does not constitute legal advice, and should not be relied on, since each state has different laws, each situation is fact specific, and it is impossible to evaluate a legal problem without a comprehensive consultation and review of all the facts and documents at issue. This answer does not create an attorney-client relationship.
Cute concept, but it is fraught with legal problems under copyright, trademark and right of publicity concepts. Most famous theme parks make significant revenues by licensing their trademarks and decorative themes to hotel operators, Neither the theme park owners nor the hotel operators would be pleased with your plans. Even if you have valid defenses to claims of copyright and trademark infringement, you would in all likelihood need to pay to defend an expensive law suit.
Note that you have some fundamental misconceptions about IP law. First, so far as I can tell, Peter Pan is not in the public domain. Second, even if you do not use characters, if the design themes that you use are obviously taken from Toy Story, Peter an and other such works, you are engaging in infringement. Third, even a "concept painting" is protected by copyright---whether or not it was used in the movie.
If you want to pursue this---and I doubt that this is a good idea, you absolutely must retain experienced IP counsel. And you might want to consider attempting to obtain licenses from the theme park operator and owners of the film copyrights---other hotel operators have done so and perhaps you could succeed. Without licenses, this is a risky business indeed.
Attorney Koslyn is correct - no one, obviously, can pass on whether your artwork and room configuration would infringe anyone else's intellectual property rights until your work is compared with the original and your marketing of your rental unit is assessed.
That being said, I think the concern expressed by Attorney Ross is unwarranted.
So far as I'm aware, copyright does not attach to the appearance and/or configuration of a fictional room that's portrayed in a movie or book. If "especially distinctive," the fictional characters that appear in a movie or book are copyrightable seperate from the work in which they appear. But is a fictional room seperately copyrightable? I doubt it very much.
As for Peter Pan, the story and the artwork in the original story [and all subsequent stories and artwork first published in the US before 1923] are most certainly in the public domain. Which means you are free to directly copy any of that artwork -- and to create your own Peter Pan images based on that artwork or based on your own whim. You may NOT, however, "recreate a painting from the fifties" that shows one of Disney's concept designs for its version of Peter Pan. Copyright [very likely] still attaches to that version.
As for painting a room "reminscent of pixie hollow from the Tinkerbell movies," my approach would be the same as that for Andy's room in Toy Story -- no copyright attaches to the appearance of a fictional room in a movie.
Which leaves the elephant in the room question: assuming your rental unit is painted all snazzy as you describe, how are you going to advertise it? You CANNOT say or imply anything in your advertising [in print or in person or any how] that would lead a consumer to believe that you or your rental unit is associated with or sponsored or endorced by Disney.
In sum, you need an intellectual property attorney to pass on your room designs and on your advertising. Good luck.
A few comments might be helpful. As to Peter Pan, I assumed that the question relates to the Disney Peter Pan film and it's spin-offs rather than the original book. It is true that the original book is in the public domain, but derivative works by Disney, including the famous cartoon movie, are not. To the extent you would use concept designs by a Disney Artist, your use of the design would likely violate copyright
As to, scenes from rooms depicted in movies, my colleague and I can agree to disagree. Original room designs including murals of clouds and other such adornmnets certainly can meet the originality requirement under copyright law. Note in this regard that the design behind rooms depicted on Toy Story have been repeatedly been used in advertisements for toys and other merchandise, and these designs have been licensed for use in hotels who have marketing colllaborations with DIsney. Thus, with due respect to my colleague, I think there is a potential copyright problem here,
I also agree that there may be trademark issues here as well. The designs may also have been incorporated into and/or may constitute trademarks.
The bottom line is this--if you are running a commercial rental property, you should retain IP counsell to advise you before you go down this path.