Definitely go for the second edition, since it includes everything from the first.
The second edition can easily be played 2 player with a few tweaks. If you play the second edition without the "Raid" option, you're essentially getting the exact same experience as 1st edition. Alternatively, there are a few players here on BGG who really enjoy using 2 Captains each, then using the lower of the two Captain scores as your final score.
thank you! now to find the game at a reasonable price