I have seen some hero and villain versions so i came up with my one version
My Favorites are Morte, And Jan Jansen

My favorite NPC in BG/BG2 was Imoen.

jan jansen and Edwin...

Mazzy and Jan Jansen, although I have neither in my current game actually because I decided to try out new characters.

Dak'kon, Morte and Annah... ok, all NPC's from Planescape Torment. The best BGII NPC's are probably Minsc, Jan and perhaps Viconia.

Minsc and Boo.

Depends on what you call an NPC. Does it have to be someone you can add to your party ? If not, my vote goes to Harold. The ghoul from the Fallout series.

Mine is Archangel Tyrael from Diablo 2. he is the only western heaven being ( Shinjuko as we here pronounce it) who seem to actually show himself in mortal realm and actually help human beings.

I'll second the Planescape gang, but I have to give a shoutout to Vi Domina, Wizardry 7-8.

<font color="gold">All the NPCs in Planescape, followed by Jan and Minsc in BG2. [img]smile.gif[/img] </font>