Want to release old work-for-hire song

I am wondering if anyone here has any advice on this:
 
I wrote a bunch of songs for a video game for Disney Interactive way back in 1997. They were work-for-hire; I got paid for them and relinquished ownership. I supplied Midi and lyrics and their music guy did the arrangement and production. The game didn't make much of a splash, was never heard from again, and none of the team who worked on it were still around much after its release, (though there is a tiny smattering of fans who still remember it).
 
Fast forward to now - I have re-written one of these songs a bit, recorded my own version of it, and hope to release it in my next album later this year. I would be extremely surprised if anyone at DI who was involved with that game is still there or has ever even heard of the game. My album will be released on a local boutique label, and while it will be an official release, with some physical discs produced, reviews solicited, and available on iTunes, Spotify, etc., very very few people will buy it or even know it exists.
 
Questions: Do I need to bother to Harryfox this old song? Is there some kind of rule that says if you wrote it for hire twenty years ago and it has never seen the light of day and almost no one will hear your new version of it, that you can do so? Should I let sleeping dogs lie and hope Disney never notices? It seems so unlikely that someone who knows I wrote the song for them AND cares if I acquired the rights would ever catch wind of it. If I contact them to go the legal route, am I just asking for a huge hassle that could be avoided by flying under the radar? In the event that I strike gold and the song or album gains a lot of attention for whatever reason, am I going to be in trouble then?
 
I wrote a piano piece based on the Windows XP startup sound, and other Windows sounds, and it's gotten significant attention online over the years - I happened to work at Microsoft when I first released it, so I asked their legal people whether I should track down the people who wrote those original sounds (NOT Brian Eno, contrary to popular myth!), and they told me to ignore it, that I should only involve legal if someone takes notice and inquires, otherwise probably no one wants to take it on as part of their busy work lives. Which is why I'm wondering if that's the case for this song too.

I am not a lawyer, but I'll throw down a "common sense" argument.  If the song does not attract any attention and just sinks away, nothing will happen.  If it gains any buzz or glory, you will be sued by Disney (not a good thing).
So your efforts will get you nothing or trouble.  Sorry not to be more upbeat here.

if u wrote it, did they give u any writing credit?  if u don't expect it to get big, then go for it and hope they don't want the small amount of money it made... but i would try to ask them for written permission.  

If you actually re-wrote it it would be a different song.
 
If you re-arranged it, it's the same song.
 
If it's the same song (lyric & melody) then you have no right to record and sell it without paying royalties to the owner of the song.
 
Do what Herb (guitarhacker) says.

Harry Fox.  As above, you aren't likely to get in trouble, but you'll do yourself a favor by buying mechanical rights at about 8.5 cents a copy.  That is $85 or so for a 1000 CDs, if you print that many.
 
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