Hi!
Wonder if you've already decided by now... If not, I would definitely recommend the first version of the single, with three songs, even though you already have Happiness Is a Warm Gun. You'll want to own the single version of Last Night on Earth. The other single has every song labelled as a "Remix", so there's not that much U2 participation in there. It serves as a reminder, as in "oh, right, they were doing this in the 90s", but the music is mostly just bad. Definitely buy the first version, all the good songs are there. And with the first single, you'll get the beautiful digipack...