Must say those games are some of my favorite. Each have their own relative pros and cons but all are great.
The BG games are probably the best in terms of storyline and side-line plots/quests. The disadvantage to me is that to start with you only get to customer build one character with few custmoer options (BG2 is better) and have to pick and choose your party as you pick up NPCs along the way. There is nothing wrong with that, but party delevopment takes longer, but you do get some some moments as the party interact with each other. Evil characters arguing with the good ones. And there always Minsc, the mad ranger with "Boo the Space Hamster". You'll find out.
In the Icewind Dale games, although more linear, you get to customise all 6 party characters right from the word go. Which is better if you like to balance your party to different tactics from the start. Stealth based, Magic, Clerical, full frontal assault, mixed.
Make sure you have a thief with high lock pick and disabled traps.
Tatic hints. Well I was going to put some in but then decided to let you work it out for your self
PS:Torment is an odd ball as you get to change your main character's primary class during the game. Not a game I've played as regularly as the last 2 series.
Neverwinter Nights is also awsome, similar to BG as it's less linear and also uses newer D&G rules, and has better graphics. Something to watch out for with an older PC.