Addressing the game from the modern gamer perspective. This game is a proto-crpg and there is nothing "classic" about it. You have choice of 2 classes - choose fighter if you want to suffer and don't get anywhere or choose a mage and break the game with magic amulet by turning into lizard (and vastly increasing stats) in order to make this title winnable. I don't even know if there is a way to play this game without cheesing. Before any "meaningful" choices of how are you going to approach the dungeon exploration, you're most likely going to die from hunger, wandering largely empty overworld. Cities are only text screens with items available for sale (and that is mostly food and 3 weapons maybe). Castle of Lord British is another text screen asking you to kill another random monster as part of your quest. Once you kill final monster from Lord British's selection, you are given the title of Knight and the game ends - get lost now. You can play if you are crpg historian (more like archeologist in this case), but otherwise, I beg you - respect the finite amount of time the life gives you. You're not missing anything by skipping it.
Ultima 1 - You have an overworld map with different cities, castles and other points of interests, however what you explore on one continent is simply repeated on 3 remaining continents. For example you have only 2 designs of cities, each appearing on every continent (so x4). Story is stupid, and there is no proper levelling system (you just get more hp by visiting dungeons). Only progression is based on money gathered, which you spend on transportation (that's actually cool) and better gear. The game fortunately is not too annoying and doesn't overstay its welcome. Ultima 2 - With different time zones (game includes time travel), the exploration feels more meaningful, as there is more variety between locations. Story is even more nonsensical that the first one. By far the worse part of the game is it's progression, which is again based on earning money like in the first one. However the money earned does not even cover properly your food expenses. You will be frustrated by limited resources, lack of foes to get gold from and some enemies that paralyze your legs with very annoying sound. The game frustratingly prolonged by the above mechanics and you will be sick of it. Ultima 3 - Overworld finally seems more fleshed out without copy & paste cities, gone is a lot of sci-fi nonsense. The game levelling system impacts your health (yay!) but not your stats (are you kidding me?). Story is just you finding stuff, so it's nothing to miss. Game relies on party system with 4 characters that you create - you have some unique classes to choose from. Unfortunately experience is allocated to character who gets a kill, so you will be struggling with levelling some classes until they get some more powerful spells and you also have to allocate food across all 4 characters. If you lose a ship during game (due to maelstrom), you might wait for hours for next to show up (frustrating). Overall, play these games only from historical interest. Otherwise, don't waste your life.
If you don't have this game yet - buy it before Beamdog puts their filthy hands on it (and you'll be offered exactly the same, but overpriced). Game shouldn't be much of a problem to run anyway, and Beamdog won't enhance the graphics even to the level of NWN 2 (they never do). As for the game, the main campaign is okay, although not very memorable. This isn't Baldur's Gate and you won't be gripped by its story. Even Hordes of Underdark (considered the best out of NWN official modules) cannot compete against BG in my opinion. Gameplay-wise, this game rocks. It is full-blooded RPG with tons of options, items, spells etc. It is one of the closest conversions of Dungeons & Dragons to your home computer. And there is LOTS of different mods and modules created by users. As far as I am aware, people also play online even to this date. In short - MUST BUY IF YOU ARE AN RPG FAN!