santata: Probably not the worst on gog, but from what I played: Baldur's Gate (the first one, can't comment on the second one yet).
The pacing of the game drives me up the wall. Before BG, I played Planescape, which had pretty good pacing, thanks to the game having sprint. I didn't play long (beginning of the second act), but the difficulty spike the game suddenly gets is unbelieveable. One area you're fighting wolves, which are piss easy to kill, then you meet a group of orcs-goblins whatever and your party gets annihilated within mere seconds. Also, not being able to talk with your companions whenever you want was also a punch in the stomach after PST.
I tried to play the game 2 times (GoG version and the new Enhanced one), I gave up both times. I read the story in wikipedia and I'm hoping the second game is actually as good as they say. I'll have time to play it during the summer.
I couldn't finish the first one either. Too much dead filler space.
The second one was more compact and infinitely better.