One of the first games I ever played that tried to present itself as a unified experience was Legacy of the Ancients, released back in the Day (the Day in question being 1987). It had a fun and cohesive storyline, the best graphics of its time, minigames that were fun and were integrated into the main game well, music that fit the mood, and fun sound effects (the swamp squishing between your toes goes SPLAT! SPLAT! SPLAT!). Even the copy protection was integrated into the gaming experience.
Needless to say, I like that kind of stuff, and LOTA was the first game to “wow” me with the sheer level of detail it provided in an attempt to present a cohesive game world. It’s been a while since a game has knocked my socks off in a similar manner.
If you want to try Legacy of the Ancients (and you should), you can download the Commodore 64 disk images from the unofficial official site. However, the site suggests PC64 or CCS64 as the emulator to use; I disagree. VICE runs the images well without the need for a patch and is free. You can also save state right from the emulator, making it unecessary to deal with LOTA’s slow save process (those old 1541 drives didn’t do anything fast…)