Would I need to get permission to use the speech samples from Discs of Tron in a song I'm composing? Would Bally/Midway even care if these samples are used in a song that might be released commercially?
Even if someone wants to use it commercially, you're still pretty safe. It's not worth huge companies' time to go after small-time folks... you'd have to be making enough money for them to see the opportunity/viability in going after you.