Hi again, Sir G. As the others mentioned, IWD differs from BG2 as you start at 1 and go on from there. Goblins and Orcs can actually kill you. But then you get tougher, but, gasp, the monsters get tougher. You buy and sell to get better stuff, kill more things, get tougher, and, gasp, the monsters keep getting tougher. Where did they learn this stuff, from some sick, demented old DM like Keraptisdm??
You'll enjoy this game quite a bit. A lot of dungeon trolling, so it's different than BG. Notice I said different, not better. Each game has it positive points. You want to see someone level up fast? When you get around 7th level or so, reform your party and bring in a new, first level character to your party.