The Mass Effect series is a good example of mixing genres combining all the aspects of adventure, shooting and role-playing in addition to having a pretty good and fairly detailed storyline. The concentration is on character development and through conversations allows you to choose between the path of a paragon or a renegade. The direction you choose to go in somewhat affects the course of the games and gives them great replay value. You can import your Mass Effect 1 character into Mass Effect 2, so you should consider playing that one first. A save file for this should be in your Documents Bioware folder unless you've deleted it.
The setting for the games is the Milky Way Galaxy and your character, John/Jane Shepard, is the commander of a unique battleship called the Normandy. Within the galaxy there are many star clusters and within the star clusters are many planets. In Mass effect 2 there is an overall main mission and in order to achieve it you need to assemble a team of specialists by locating them on specific planets and convincing them to join your cause. Some of these are from the vast array of alien species populating the galaxy and each team member has their unique abilities. Two of these characters are imported from the first Mass Effect. You must also do a special mission for each member in order to gain his or her loyalty and open up a locked ability.
Along the way you will also pick up side missions which give you experience points, monetary credits, valuable minerals, armor, weapon and ship upgrades, all of which allows for levelling up both you and your squad members. Shepard's choices of interaction with the team, the crew and those he meets along the way will determine team loyalty and open up romance options.
There is a vast array of information about the races, the planets and technology. Too much as far as I'm concerned, but you don't have to read it all if you don't want to. It's just an added dimension that may give you specific information about the defenses of the enemy that you will be facing during a mission. There is also the rather mundane chore of scanning and mining valuable minerals from the planets, a necessary task in order to purchase certain upgrades.
I thought the combat portion of this game was quite well done. The main defense is to take cover while engaging the enemy rather than adopting a kamikaze style. This is much more realistic and works very well. In addition to weapons, Shepard and his team have accessible biotic and tech powers, which can be called upon in a fight. Although your squad members will use these at will, you can also control when they use them as well as position your team in the battle. For AIs, they actually behave fairly well on their own, although they have a tendency to be mavericks at times which can quickly put them out of commission. Directing the battle yourself by combining the right powers of the team can have a devastating effect on the target.
Getting a handle on picking the right conversations is a little trickier to figure out. Being the thorough person that I am, I like to explore all the dialogue, but the game is not set up for that approach and you can't develop the paragon or renegade characteristics of Shepard by this approach. There is much more importance attached to this than in Mass Effect 1 and it will determine how certain things turn out so you need to pay attention to this aspect. I found trying for renegade a little harder as my instinct is to investigate and I kept getting paragon points when I didn't want them.
The graphics are pretty good for the most part, although in the beginning the use of severe close ups had me wondering, but over time I stopped being so aware of it. I was super impressed with the way they developed Shepard's facial features over the course of the game as he becomes more battle hardened and experienced.
This is a vast game and you can only touch on all its various aspects in a short review. There's no question you get your money's worth and you could be playing this game for a long time. It's packed full of exploration and characters to the point where you really need to keep track. There are also several classes you can assign to Shepard thus extending the value of replaying for a different experience.
The story picks up where it left off in Mass Effect and I would seriously advise playing these games in sequence to get the best from them as there are character and plot references that show up in the second. This is one of these games where you should do a little research first in order to know just the basics of how your decisions will affect the direction of the game. There is also extra free content and by signing up with Bioware's Cerberus network at "social bioware.com" you can download this as well as buy extra DLC. After this when you fire up the game you will be connected to the site, but you can turn this off in game if you don't want an internet connection running.
There are one or two bugs, not surprisingly, but all in all I highly recommend all games in the series.