I played too many RPGs to have a favourite, really. I'd say favourite series are Golden Sun (take out the DS one, crappy) and Final Fantasy, which was gladfully not the final dream of Square
RPG is my favorite genre and I would like to mention a few rpg games I was impressed with.
1. Fallout 2 - post apocalypse nuclear RPG
Game: Fallout 2 Publisher: Interplay Developed by: Black isle studios Year: 1998
This is definitely the best RPG that I have ever played. Fallout 2 is simply unsurpassed. In its own time and even today, he laid the foundation of modern RPG. At that time it was a revolution in every sense.What made this RPG famous is definitely not a graphic, but story which set up a homework for all future RPG games.
2. Baldur's Gate (series)
Publisher: Interplay Developed by: BioWare Year: 1998
One of the finest RPG games ever.It's a shame we do not have the opportunity to see such a pearl again.It appears that the year 1998 was the golden year for RPG. Today's RPG's can not be compared with its predecessors.
3. Planescape: Torment
Publisher: Interplay Developed by: Black isle studios Year: 1999
Another pearl in a row. Black isle studios strikes again What made this game fantastic is a plot.It was considered to be the best role-playing game of 1999.
But since this is not a top 10,I will proceed in the order,but I'll just mention them: Arcanum,Final fantasy 1&2, Diablo1&2 (action RPG/hack and slash), Dungeon Siege 1&2.
My favorite RPGs are definitely Fallout 3 and Fallout: New Vegas. I've made mods for new vegas, and I've played both of them all the way through at least 10 times each. Hopefully Fallout 4 comes out soon too!
The Fire Emblem series, all the ones made in North America, at least, Pokemon, and X-Com: Enemy Unknown (Remake of first X-Com game from 20 years ago).
It would have to be any of the games in the Elder Scrolls series or Fallout series. They are both are pretty well written, have nice music and quests overall.