I am a complete newbie to this game, although I do have a small amount of experience with RPGs. I was planning a party with 2 Fighters, 1 Cleric, 1 Thief, 1 Mage but I was not sure what to use for the 6th slot. Any Tips about character creation, basic combat techniques, etc. would be much appreciated!

Thats exactly what I have for my party, except I have a ranger thats experienced with the bow. He has a pretty high dexterity and like 18/76 strength. For the 6th person, I personally would recommend a bard. My bard can pretty much identify every object I get ahold of. This cuts down on wasting money at a priest to identify something or wasting spell slots with the identify spell. There seems to be a ton more magical items than in Baldurs Gate so a bard comes in very useful. For me at least. Not to mention a bard can also learn mage spells. A bard is pretty much "A jack of all trades, but master of none". Bards are well rounded characters and very helpful. I wouldnt trade my bard for anything Hope this helps

Hey, how bout an all Bard party then for a challenge? Let 2 be your spellcasters, and the other 4 concentrate on fighting.. Or maybe 5 bards and a thief for the traps and such. I think i'll give that a try when i beat the game. These damned Tarnished Soldiers (or something) are tough as hell, i can only hit them with melee weapons, and that pisses me off.

Your party is the classic set-up and should work ok. Personally, I would have more multi-classed characters--only because Icewind Dale is fairly dangerous, and though you will have to interact with many NPCs with no violence involved, for the most part, combat is king here (in my opinion, of course; the fact that reputation is not a factor in IWD seems to indicate that). Hence, I would recommend 2 pure warriors, and having most of your other characters multiclassed (say, 1 or 2 fighter/clerics, 1 fighter/thief)--with the exception of a pure mage, who I think should be specialized to that one class so he/she can access higher-level spells more quickly since his/her exp points aren't being constantly divided amongst the two or three classes (I'd recommend a specialist mage, by the way, since you get extra spells--just know what school of magic you'll lose, though, so you don't get upset when you try to write a neat spell in your book but can't because it's from your opposition school). In any case, whatever you decide to do (cause no one party is best), just be prepared to fight--i.e. ask yourself how well your party will do when the going gets tough. If you think more than one character won't be able to hold his/her own, I'd recommend included some multi-classed characters--fighter plus something else. Good luck (by the way, see a similar topic posted previously here).