some nice suggestions here, but not many RPGs, so here are a few:
the Ultima series was groundbreaking for its time, and while the early installments are grind-heavy and feel quite dated, Ultima VII
is still considered one of the best games in the cRPG genre. while this is a DOS game, the preferred way to play it is by using Exult
, so this particular suggestion might not be so great in this case.
so, for DOS-specific RPGs, Ultima 5 is really good, as is Ultima Underworld
and its sequel
, which is in fact even better. these games feel surprisingly fresh even now, especially for their suggestive environments, with levels of interactivity that are in some aspects completely unrivaled by today's graphics-heavy games.
The early Might & Magic games can still be very fun. can't recommend MM1, because they were just starting to learn how to make games, but MM2 still looks colourful and sweet, and there are many great adventures to be had. later installments are even better, until the series deteriorated around part 8 and was later cannibalised by Heroes of Might and Magic. Might and Magic X, which was released in 2014, feels like a cheap joke when compared to these older titles.
now, Dragon Wars
is a mix between the early Bard's Tale games and Wasteland. it looks dated and requires an instruction manual to actually be able to progress, but the gameplay and the story are superb. I still play it sometimes, like once in a few years. an 'intelligent' approach of using a variety of assets that are available to the party (items, spells, character skills, lores and attributes) should be taken to get the best solution to a problem or to find hidden secrets, but an aggressive approach will often work as well, because the game is pretty open-ended. for example, while this will not be obvious from the start, there are many different ways to escape from the prison settlement that you're thrown into at the beginning. there's a huge, open world with a simple but suggestive story based on Sumerian mythology, the environments are surprisingly interactive at times, many fights are really epic, there are many hidden, optional challenges to tackle, there are pirates. great underdog.Anvil of Dawn
is a nice, action and puzzle-heavy, hard dungeon romp with a dark, brooding atmosphere, great visuals and sound. if using a non-GOG version, the game must be patched or it breaks at some point.Betrayal at Krondor
is a classic story-heavy RPG with a rich world and some great writing. it's really good, if you manage to overlook the awfully, terribly ugly 3d environments.
there are literally hundreds of other great DOS games, but I think that's enough for now.
edit: and if you've taken ScummVM for a ride, be sure to take a look at Zak McKracken and the Alien Mindbenders
. it's a bit less-known than other Lucas games from this period, but it's very very funny. and very strange.
oh, and the Gobliiins trilogy, and Full Throttle and The Dig are cool. and try Quest for Glory series for an epic adventure-RPG mix.
edit 2: aaand Discworld is funny like hell.