As previously mentioned, if you are running Widescreen, get the Widescreen mod, and the Widescreen GUI mod if you want it to display correctly in widescreen. But for the Widescreen GUI mod to work you can only run at a max res of 1280x800. Still looks great at that res though IMO.
If you have any issues, check out the Baldurs Gate forum on GoG, most issues have fixes. I had problem with the 'fog of war' being a little corrupted but the fix was as easy as changing a setting in graphics options.
I've been playing games for a long time, but missed BG when it came out. So far I'm really enjoying it, so I wouldn't say it's nostalgia at all. I spend more time playing 'retro' games that modern ones...