Most of Mass Effect's gameplay is split between walking around, gathering information, and intense vehicle driven and squad level combat. The amount of time you have to spend talking to people and gathering information may be a turn off for players that want a more action oriented experience, but for those looking to explore the kind of deep and engaging worlds that Bioware is known for, this should be right up your alley.
When things do get violent, the combat controls are extremely well implemented. It's easy to make use of the duck and cover system, which allows you to use things like walls, crates and boulders for cover. It's also easy to give commands to your squad mates, such as telling them whom to target, what weapon to use or what special skills they should employ. Just a quick hold of the spacebar brings up a very navigable HUD that allows you to give direction or change weapons. If that kind of detail work seems overwhelming, however, you also have the option of making your companions a bit more autonomous, allowing them to fight as they deem fit. For the most part they do a decent job of managing themselves, but there will any number of frustrating moments where they get in the way, shoot you in the back or otherwise behave in a less than helpful matter.
Despite the sci-fi setting, there's no real ship-to-ship combat in this game. When you get your ship there's a lot of talk about how technically advanced and special it is. But none of that really comes into play. Instead its only real purpose is to get you from star system to star system and provide an opportunity to chat with and get to know your NPC crew. It does the job, but it also feels like a wasted opportunity for your character to do something worthy of James Kirk. That said, there are around a dozen different star systems and clusters to explore. Only a handful of these systems are tied into the main storyline, the rest are there to serve the needs of various side quests that you can take on or ignore at your leisure.
Getting from one solar system to another is extremely easy. Your ship has a navigation tool that allows you to zoom in and out via the left and right mouse buttons and a click of the mouse is all you need to select a destination. Once you've arrived in a system, you can select any of the planets surrounding the system's star and get baseline information about that world. Most planets are uninhabitable, but a few allow you to conduct surveys which result in finding deposits of precious metals, alien artifacts and other clues. Still fewer planets allow you to land and explore the surface. Usually when landing is an option it's part of a side or main quest, but it almost always involves dropping from the ship to the planet's surface in an armed all terrain vehicle (ATV). From it you can explore the planet's surface for still more minerals, alien artifacts, etc. This part of the game is both fun and very reminiscent of the old PC game Starflight (1986).
All of this, however, isn't what makes Mass Effect the kind of game experience that any fan of RPGs should long to play. Really, it's the fact that Bioware has allowed the galaxy that they've created to breath. When you first arrive at the central world of Citadel, it looks like it's going to be a pretty generic 3rd-person shooter with a little talkity-talk as you go. But as you explore the Citadel an entire galaxy opens up to you.
The alien races all have incredibly rich histories. Every character of consequence has a deep personal history that offers clearly defined motivations for their actions. And the actions you take in the world have consequences in the world appropriate to their scale. (If you're just doing one person a small favor, they'll remember you. But if you do something big that gets everyone's attention, most everyone will comment on it.) With characters and cultures so well defined, it's easy to get lost in the world and get to the point where you actually care about what happens to the people in it.
