A game for the history.
As many reviews says, Fallout 2 is Fallout 1 with improvements. Well, not exactly. The gameplay is exactly the same, abilities and other stuff, but there are more feats.
The story is different, you are a descendent of the hero who saved the Vault 13 (and other towns) from the "Master" in Fallout 1. As usual you begin with the task of being chosen for retrieving the "G.E.C.K." to your village to save it. You start travelling all over California (or whatever it is) and discover new towns / locations, do side-quests, help people (for good or for bad), or just kill everything you see (not a wise choice but you can do it). The moment you retrieve the G.E.C.K., the plot twists, as usual, and you get to investigate a secret organization called "the Enclave".
So...ok..? Why did you just give a "10" score to this 2D isometric game?
Reasons:
1-Great sequel of Fallout. A great game and this keeps the gameplay intact.
2-"Do whatever you want". In Fallout 2 you can do whatever you want. You may kill quest givers if you want. There are several ways of completing quests. You can allign with different factions who will give you different missions (I remember the city of the "drugs"). It is important to give your character a high intelligence and charisma as it will let you complete most quests in the game.
3-Atmosphere: Post-nuclear, sordid, dark. Lovely!
4-Improvements from Fallout 1: Many many locations with lots of characters and factions to interact (the game does feel a little more lively than Fallout 1). This has more weapons, more feats and more types of ammo. You can have more companions depending on your Charisma (10 charisma lets you have up to 5 companions). The IA of your companions is higher and you can manage their equipment, the only problem is that they have a limit of capacity (in Fallout 1 you give all your trash to Ian). Each companion has a unique ability (medic, scientist, etc.) and will help you if your level of that ability is not enough to success the roll. They have different personalities and some are hilarious to hear.
After you finish Fallout 2 you will want to play again to create a different character and complete quests in other manner or allign with the factions you exterminated or neglected in your first playthrough.
You will often wander why RPGs nowadays are not like Fallout / Fallout 2. The magic of any RPG is that you have freedom to make your own choices. Nowadays you have barely choices. It is obvious that in Fallout there are "better" choices and "bad" choices, but you have them and make you doubt in what to do. Very little things on Fallout are mandatory.
Enough. For any RPG fan just play this game for good.