One program that must be mentioned (yet again) is a version of that original adventure program by Crowther and Woods - Colossal Cave Adventure. In many ways this was the program that started the adventure craze on computers back in the 1970s and has become a classic on every micro for which it has been converted.
I got my copy from Advantage who charge £10.95 for membership and then £7.95 for this disc; £9.95 for nonmembers. Colossal Cave Adventure is a good version of the original. It has no graphics, and is not an easy game.
For those very few who do not know this one, you are in a fantasy world of trolls and dwarves searching for treasures through underground tunnels and caves, This version is very complete and if you have the programming skill, it allows access to all files for you to play around with - not recommended for but a very few!
Another version is on Rainbird's Jewels Of Darkness, a compilation of three of Level 9's classic adventures. This will cost you £19.95 and you get two other excellent adventures as well - Adventure Quest and Dungeon Adventure.
All have graphics, albeit fairly rudimentary, and a very good command interpreter. Whichever your choice, no adventure collection is complete without a version of Colossal Caves.