Might & Magic has perhaps one of the most impressive histories, now rivalling some of the greatest RPG series including Ultima and Wizardry, unlike those, this series was not begun back in the 70's when there was relatively little competition, but rather in 1986, when author Jon van Canegham started putting ads in computer magazines and selling the game out of his home!  It was soon bought up by a distributor and has joined the ranks of legendary RPG series.  The Might and Magic games have their own character, always having extremely excellent graphics from the start, relatively little NPC interaction, and huge worlds to explore.  While the majority of the games consist of quests involving fetching items and taking them to different people and the puzzles are few and far between, these games have an addictive quality to them which simple can't be explained.  Also, since Jon is clearly a Star Trek fan, by the 3rd or 4th installment, we've come to expect to find ourselves somewhere in outer space by the end of the games fighting robots with laser pistols, and so far he hasn't let us down.

King's Bounty is also worth looking at for fans of the Heroes of Might and Magic series, as this is the precursor.  If you haven't seen it yet, the similarities are striking despite the number of years between their development - it was definitely a game ahead of its time.