I am a big fan of rpg's.  Some of the best hours of gaming I have played were spent finding treasures and fighting all sorts of beasts.  In the last two weeks, I have been playing the best rpg I have ever played, the most satisfying.  After putting in almost 15 hours in this game, I have finally been given an armor.  My fights against the local beasts are getting a little easier.  The map is completly useless, forcing me to remember the layout of the important landmarks.  Almost all of the npc's look alike.  But...this is the most fun I have had playing an rpg.  Of course, I am talking about Risen.  This is by far the toughest and most unforgiving game I have ever played.  And yet, I almost cried when The Don sold me my hunter's armor for 1000 gold.  I gave half my coins to get it.  It looked bad but I didn't care.  Half of the time, I have no idea what I am supposed to do.  I should hate this game like everyone else does.  But no, this is my ultimate RPG. 

So, let's get a list going.  What's yours?  Thanks for sharing.

I cant name just one. Im not going to go with the obvious FF7 or whatever.
I'll say BOF3 because i believe it was the first RPG i bought, ever and pretty damn good.
Grandia, didnt play this until it came out on PSN a few years back, but it amazes me how much better it is than some RPGS released this gen.
Fallout3 this game made me do a 180 on the whole idea of WRPGs. The best part is i never even bought it, it was a xmas gift that was given to me, because my friend was that confident i would like it, he wasnt wrong

Skyrim - it may be a generic, conformist, cliche choice, but the fact is is that it is the greatest RPG of all time. It made my 2nd favourite RPG of all time look like a steaming bag of shit. It has beautiful landscapes, a wide variety of weapons, great character customisation, shitloads of armour, countless paths to go on, infinite quests, etc. etc. Oh, and JRPGs are all absolutely terrible IMO. I have played many including Final Fantasy and they really are awful.

I am not a big fan of JRPG's myself. I finished FFXIII and bought the sequel, but I have a hard time getting into it. I must agree that Fallout 3 is an outstanding game. I really enjoyed New Vegas as well.

StIll: Betrayal at Krondor

http://www.mobygames.com/game/betrayal-at-krondor

http://www.videodetective.com/games/betrayal-at-krondor/6475

http://www.youtube.com/watch?v=43mQ-m65skI

It is always hard to chose one. Today I'll just say that my favourite rpg of all time is Dragon Age Origins, considering all its expansions, PC version.
I always loved rpgs, specially jrpgs (Tales of Symphonia and Persona 4 might be among my favourites) and srpgs (Fire Emblem: Radiant Dawn may be my favourite one) and I had little experience with the western cousins.
Dragon Age Origins has been my strongest experience this generation, to say the least.

My most favorite computer-RPG of all time is Wunderland, a german MUD: http://en.wikipedia.org/wiki/MUD
A game more of you might know is Baldur's Gate, also one great RPG-experience.
I also have much fun playing Etrian Odyssey.
If SRPG count (someone mentioned Fire Emblem), then I should add Battle for Wesnoth.

If I really have to pick just one, which is so insanely hard to do, I'm going to go with Earthbound. It's funny, charming, poignant, thought-provoking, satirical, happy, and sad all at once. No other game before or since conveyed the same range of authentic feeling or felt as emotionally satisfying to me.

Demon's Souls it is my all time favourite. Its still has the best combat system of any RPG. It was challenging but just taking down a Boss gave me a huge sense of accomplishment. Online was fun and innovative too.

It's not really hard to pick one, because my favourite game of all time is also the ultimate RPG for me as well.

I'm talking about Lufia II: Rise of the Sinistrals. It has it all, amazing gameplay, an epic and actually thought provoking storyline, memorable characters and interactions, expansive world with tons of things to do, some actually difficult puzzles with great use of on-the-fly abilities and scenario, on-screen enemies plus the game was actually challenging (unless, of course, you overlevelled, which destroys the challenge of any RPG). And all this great package can be found on a SNES cartridge .