1. I was thinking of using sprites ripped from old classic games for a fun personal side project. I notice that many of these websites that allow you to download ripped sprites demand you give credit to the ripper for using the sprites from the website.
2. Now I am no lawyer
3. but how does anyone have the right to demand you give them credit to use sprites that they do not even own? It reminds me of a video on youtube where someone had a compilation video of classic game footage. This person had taken footage from another person's video where he had recorded a video game. Everyone bashed on him once that was discovered claiming he plagiarised this other persons video. I defended him and said that neither he nor the person he "stole" this footage even owned the video game footage and no one had the right to accuse anyone of anything.
1. What the other guy said. You're going to credit a ripper, and not the original creator/owner of the sprites?
2. Right. You need legal advice before you release your fun project. One hour of a lawyer's time shouldn't set you back more than $400 or so. There's a list of game lawyers on the obscure.co.uk website. See also thegameattorney, underdevelopmentlaw, and charnelaw (if those are not listed in the obscure directory).
3. Well, the person who made the original video does have a copyright in the footage he created - the creative decisions he made (including when to start and end a clip). If his footage has (for example) a blip or fadeout at a particular point in the footage, and that blip or fadeout is evident in the second video, then it's clear that the second video did violate the first videographer's copyright. The matter of whether or not the first video violated someone else's copyright is an unrelated matter.
[Tongue-in-cheek alert] So you should rip your own darn sprites, then it'll just be you and the party whose rights you violated. A simpler lawsuit. And simpler is better (it'll make the judge happier, and you want a happy judge when you get taken to court). [/Tongue-in-cheek]