Super Wing Commander is a remake of Wing Commander I with new graphics, full speech and a new addon campaign. Well worth the purchase of a 3DO - everything is different.
There's also WC3. Wing Commander 3 3DO is, in my opinion, the finest console port ever made. Instead of making it *exactly* like Wing Commander 3 PC the team changed the game to suit the platform - they redesigned all the missions to be more action oriented. It has some really neat differences (a few different ships to fight, much bigger missions, some cutscenes removed from the PC version, etc.)