I stopped by the offical Elder Scrolls web site last night and they're celebrating a 10th anniversary this month. Part of that celebration they are letting people download the original game that started it all, Arena. (They're also giving away some cool stuff if you register with them for the giveaway contest).
The hit RPG Morrowind is the 3rd in the series of ES RPGs, Areana being the first, and quite a change from what most RPGs had been.
Just a note, the graphics are dated, and you may experience some issues getting it running as it's a DOS program (not a Windows one), but they also link to DOSBox which should be of interest to not only Windows XP/2000 users but Linux users as well, it emulates the whole processor as well as the sound and video. It runs too slowly on this machine for this game, but it may be a solution for others with faster systems (I've heard it runs slow but playable on a 1.4Ghz PC)
Some help if available in the ES Forums as well down at the bottom of the page in the Other Games section.
Thought I'd pass it along, I might see if I can get it working better for myself later today, stupid thing crashed on me as I was leaving the 1st dungeon (stupid windows).