Re: Quoting Song Lyrics (Legal issues)
I think you'd be OK with using the rhythm and rhyme scheme, Ursa, but I'd steer clear of any words which might be song-specific, as it were. Quoting song lyrics is fraught with danger, as you can't even use snippets as you can with eg poems.
Coragem, my advice would be to write your own lyrics. The word superman doesn't belong to anyone, but Superman (ie as a name) probably does. Whether any of the accompanying descriptors have been trademarked or whatever, I don't know -- you'd need to check. I'd suggest you avoid them and use your own.