Both games are good but I would still put it like this: If you don't intend to play online, to download some fan-made modules or create your own then don't bother with NWN. It's single player Official Campaign in NWN is decent but not in the same league as BG2. The strong multiplayer capabilities and the easy-to-use Toolset is the real strenght of NWN. With the Toolset you can create your own modules using the same content that's used in the OC. A very powerful tool, indeed. But if none of this interrest you, then NWN probably isn't anything for you.
But you should really get both.
IWD is on budget and so is probably IWD2 as well. And you should be able to find NWN fairly cheap as well. Just don't forget to patch it when you get it, I've heard there are some bugs in the earlier versions. All three games are very hack'n'slashy in nature.
[ 12-05-2003, 05:17 AM: Message edited by: Stratos ]