I don't know if this post is still of any use to you, as you've marked the topic as solved, but if not, maybe someone else will have some use for it in the future.
First: Of course, Hickory is correct: If you *really* want to experience Baldur's Gate 1 as it was designed, including the 640x480 resolution and gameplay limitations compared to BG2, then there is only one option, and that is to install play Vanilla BG1 from beginning to end at least once. If you have never played a BG2 game before, and you can stand the 640x480 resolution (it's doable on a 17 or 19 inch 1280x1024 screen), then it will not be a problem.
My recommendation would be to just install the Vanilla Baldur's Gate *and* BG1 EasyTuTu. Don't install any mods in EasyTuTu, apart from (maybe) the Spawn Randomizer to limit the spawn frequency.
Start Vanilla BG1, and you'll see if you like it enough to finish it as it is. If you don't, my recommendation would be to not fret about it, and switch to EasyTuTu immediately, because the BG1 story is certainly worth playing, even if you don't experience it in its original engine.
There are differences between the two engines, obviously, but for me, after FINALLY playing the EasyTuTu version after YEARS of eyeing it (I never dared to start because of the Beregost bug, let alone start while development was still in full swing), I can now say that Vanilla BG1 is a big PITA. Not because of the story or anything, but because the BG2 engine is so much better.
Previously, I didn't like the 800x600 graphics because the GUI icons move when you go from the main screen to a map, or a store, or inventory and such. Now I'm used to this. I can also see myself playing this game in 1024x768, or 1280x720 or 1280x800 in the future; probably when a new computer gets a widescreen over here. (On a 17 or 19 inch LCD, I'd recommend 800x600.)
Even the modest bump from 640x480 to 800x600 makes the graphics MUCH better, and it makes the game (the playing area) feel much less constricted. Also, now that I'm used to the somewhat smaller on-screen avatars and such, and the smaller GUI, I find the original game to be HUGE.... too huge.
Now, I actually prefer 800x600, and as said, I could see myself prefer 1024x768 or 1280x720/800 after getting a bigger screen.
Now I even haven't talked about the other engine enhancements, such as TAB to highlight objects, double-clicking in a store to purchase multiple items, and the faster walking speed (I estimate it about 40-50% faster), which greatly speeds up exploring the vast expanses of wilderness.
Now that I'm used to play BG1 in the BG2 engine, I just find the original engine inconvenient, and the resolution too low... the only reason I stuck with it in the past is because I didn't dare to run EasyTuTu. (While I posted about unstability, I think this problem is solved. I'll post in that thread when I'm sure about it.)
Post edited June 15, 2013 by Katsunami