I got BG2 a few days back and I have difficulty understanding the fighting mechanics of this game. It seems that some times my party will do ok in a battle and other times the same monster can be unharmed or barely injured through minutes of fighting. What am I missing? Is there an effective way to deal with enemies even at the beginning levels?

Thanks!

Baldur's Gate 2's combat system uses the AD&D ruleset
AD&D uses a combination of Armor Class (AC or the number in the shield icon), and THAC0 (To Hit Armor Class 0) to determine if an attack is successful or not.
For example: my Fighter (THAC0 of 8) attacks and enemy mage with an AC of 4. Because the fighters THAC0 is 8, he needs a dice role above 8 (on a 20 sided die) to hit an enemy with an AC of 0. Because the AC of the mage is 4, the fighter only needs to role a 4 (8-4=4). On the opposite end, if the fighter was attacking a mage with an AC of -4, he would need to role a 12 (8+4=12). I probably made that sound very confusing, so I recommend you read this very well written guide:
http://www.gamefaqs.com/pc/258273-baldurs-gate-ii-shadows-of-amn/faqs/34147

and have fun with an amazing game :D

Thanks blackakari! I also downloaded the massive manual and so I am going through that also. This game is very different than other RPGs I played so it might take some time to get used to. Thanks again for your quick reply!

Are you getting a weapon ineffective message in the information bar at the bottom center of the screen? Some of your characters may be unable to damage the monster at all.

Some monsters require magical weapons of a sufficient level to hit e.g. requires +1 magical weapon or +2 magical weapon etc.. Some monsters are immune to magic spells. Some monsters are immune to magic spells, but only of certain types.

I believe that if you pause the game, you can mouse over the creature you're trying to attack and hold TAB. This should give you a general idea of their current hit points, e.g. "slightly wounded" or "almost dead" etc.

Try pausing the game by hitting the space bar

Thanks guys I am now used to the basics as I have been playing for 5 or so hours now. Would you say there is a benefit to taking everyone you can to join your party? For example I came across a blue chick ( Cant remember name) about to be burned and rescued her and allowed her to join my party. What are the benefits of adding everyone over selected few? Thanks for your replies!

I also noticed that there is an option to "level up" but when i click on it, I do not have points to chose from to add to my skills. What am I missing?

You only get 6 members. You'll want at least one cleric, a mage of some sorts, and several fighters.

And Your not missing anything. Not all classes get a weapon point when they level up.

The only thng you are missing is that level ups mostly provide static bonuses. Whereas on say Mass Effect you get to choose what skills improve when you gain a level, here your class determines what and how certain stats improve, and the only thing you really get to distribute are weapon proficiencies and thief skills.

Anyway, the blue chick you were talking about is Viconia, a Drow cleric. She is very evil, and in fact you lose two points of reputation for recruiting her. She is however, the only pure cleric in the game, and her turn undead ability will let her take control of them if her level is high enough.

Just to put in my 2c regarding your question about whether you should recruit everyone or not:

You can have a maximum of six characters in your party and I would definitely recommend traveling with a full party whenever possible. The game was designed with a well-balanced player-controlled party of six characters in mind, so that will give you the best chance at beating its challenges. Well-balanced, in this case, means you should at least have the four main fantasy archetypes (Warrior, Healer, Wizard and Rogue) covered. Which, in AD&D/Baldur's Gate terms means that you should have a strong Fighter or Paladin, a Cleric or Druid, a Mage and a Thief. There are many recruitable NPC's available in BG (25 in total), so there are plenty of options in that regard and getting to know each one's personality and skills is one of the best parts of the game.

Remember also that you don't need "pure" classes to fulfill the needed roles -- a multiclassed Fighter/Cleric, for example, with a decent Wisdom score (let's say 16) will do fine as a healer. There are, of course, certain advantages to having pure classes in some roles, but it is by no means required. Just have fun with it and remember, if you only want to replace someone temporarily, to leave them in a place that is easy to find and get back to (for me that is often the Friendly Arm Inn) so you can pick them up again at a later stage.

OP was asking about BG2, not BG1. :)

sorry I keep mixing them up

Also try buffing your party before fights, any priest (your blue chick for example) should be able to cast bless and chant on your party. Also using crowd control spells such as hold person or command on strong enemies, while you pick of the casters for example, can do wonders for a beginning party. Lastly casting silence on those pesky enemy casters does wonders too.

lol blue chick almost as if talking about smurfette ;p

Just a word of warning. You want to try and keep the alignments consistent with the party otherwise the party members may lash out against each other and fight to the death.

A good example is that drow (Viconia) you met is part of a race that is hated because of how evil they usually are. You meet a Paladin (lawful good aligned) who wants help with something. If you let him join the party he will make comments occasionally on his dislike of your choice of letting Viconia in the party. Eventually the two will go to blows and you have to kill one.

Also level ups grant mostly passive bonuses. A lot of times you get a better THAC0 or saving throws with the universal better hit points.