How do I handle using an image?

Fair use

This link might also be of some use.

Trade marks

If you’re not making very much money from your web site, and you’re copying the picture in its entirety, you’re probably pretty safe for one reason or another.

Taking two copyrighted works and combining them, or taking one copyrighted work and altering it is creating a derivative work, which is one of the exclusive rights that a copyright holder has (the most familiar being the right to copy). Making an unauthorized derivative work is copyright infringement just as much as making unauthorized copies. The first link that @sebastian_von_tulu posted explains when you can defend yourself against copyright infringement claims, even if you have made unauthorized copies.

But as a practical matter, if you’re not doing anything particularly offensive or profitable with the movie posters, you’re rather unlikely to be sued for using copyrighted images on your web site. And before a suit, you’d probably just get a threatening-sounding letter from some very expensive lawyers for the copyright holders. I wouldn’t worry about that too much.

Also, what do you mean by the rules with trademarks? They’re intellectual property, and as such, they can be misused or infringed upon. Are you offering a product or service with a logo that looks like someone else’s trademark, or are you just using others’ logos to poke fun at their products? We’ll need a little more to go on.

Sorry, that mod was deserved. Copyright law is complex and require some research. @Dominic gives great advice.

Copyright law changes with the way you use the image/media. If your intention is to make a profit, you need to be much more careful about how and where you use copyrighted works, and get proper permission. Artistic or reporting purposes are treated differently by the law.

From copyright.gov:

How much do I have to change in order to claim copyright in someone else’s work?
Only the owner of copyright in a work has the right to prepare, or to authorize someone else to create, a new version of that work. Accordingly, you cannot claim copyright to another’s work, no matter how much you change it, unless you have the owner’s consent. See Circular 14, Copyright Registration for Derivative Works.

How much of someone else’s work can I use without getting permission?
Under the fair use doctrine of the U.S. copyright statute, it is permissible to use limited portions of a work including quotes, for purposes such as commentary, criticism, news reporting, and scholarly reports. There are no legal rules permitting the use of a specific number of words, a certain number of musical notes, or percentage of a work. Whether a particular use qualifies as fair use depends on all the circumstances. See FL 102, Fair Use, and Circular 21, Reproductions of Copyrighted Works by Educators and Librarians.

Good luck