Alright. I was not born for some of these, and in my native country in my youth nobody knew of them. Help me get into the Gold Boxes.
I've played and enjoyed newer, loosely connected things like M&MX and KOTC. I got some way into M&M6 and Wizardry 8. AD&D is great. I don't mind combat, but hundreds of battles one after another can get a little draining. I don't mind old graphics and the like, but sometimes the unique interfaces these older games have can really be a drag - that can be really subjective, though (E.g. UU and ROA were fine, BaK was a bit annoying, Darklands trying to real time combat it pissed the crap out of me), and I'll persevere if I know the game is good.
Which GOG set should I get, and what should I start with?
The second set is the one with all of the Gold Box games. It also has some bullshit called Hillsfar, but I don't think anyone fucks with that--it's like some sort of D&D themes lousy arcade shit. The other two sets are totally different games.
I think everyone recommends starting with Pool of Radiance, which is probably your best bet. I've been playing it for a few days now, and after getting past the interface--and having to look shit up on a PDF book for all the journal entries--it has been a pretty solid game. Interface is entirely keyboard, but by and large it's about the same as the Might & Magic Xeen games, which was my ideal keyboard interface, and, though PoR's is inelegant at times, it's not too bad.
Game holds up real well--a lot better than the '80s Ultima and Wizardry games, which I was complaining about earlier in the thread (I've got a chip on my shoulder about those games in particular--they are shit). The combat is fairly simple but has some fun wrinkles in terms of positioning and shit. Also D&D spells are there, which is good. There's a decent number of fights, and it's a big focus of the game, but so far it hasn't felt grindy. Maybe a little bullshit at times, but that's only been for a handful of battles.
I definitely recommend using the gold box companion
http://personal.inet.fi/koti/jhirvonen/gbc/ if only for being able to see all your dudes' hit points at all times, which is real helpful for combat.
Also the Forgotten Realms Unlimited Adventures--which is included in the same bundle as PoR and is essentially a PoR toolset--actually seems really cool, and it looks like there's a good number of user-made adventures, including adaptations of a lot of old AD&D modules. I'm really excited to try some of those out.
Buy the shit and play it. It's got elves and shit. I don't think you can fuck them tho.