Starflight

The Good
The Sega Genesis port of the DOS game Starflight is most probably the best version of this stellar game. The graphics got a major boost, and all the content is here.

Scientists in your home colony have just discovered that your system's sun is going to go nova, and so you are given a barebones ship and the task of finding other colonizable worlds....But there's more to the story than that. It's quite good, I won't spoil it.

Essentially, this game plays a lot like Star Control 2. You explore a truly massive sector of the galaxy, entering over 270 solar systems, and exploring over 700 planets. You can land on these planets to mine for minerals, capture specimens, and occasionally find rare and useful alien artifacts, which can be used to endow your ship with extremely useful alien powers. As you make money, you can upgrade your ship, your landing craft, and hire and train better crew members. There are several alien races to contact and deal with, and you can make friends or enemies of them by your actions.

The Bad
The sound and music are good but unremarkable. The ending isn't spectacular, but you don't really play this game just so you can get to the ending. The game can be difficult if you're not careful, but that's probably not a negative point for most people.

The Bottom Line
This game is truly staggering in size, enormously addictive, deep, and non-linear. Certainly one of the best Genesis games out there, not to mention one of the better PC-to-console ports I've seen.