It is funny, I'm not a Star Wars Fan but KOTOR games are pretty up there, just because both were good games and the second one even with being unfinished had some very cool writing, and Kreia seemed to hate Star Wars more than I ever could, heh.
Fallout games are good as well. Loved the first 2 Fallouts. Three wasn't as bad as I thought it was going to be (I found Morrowind boring and didn't play Oblivion until very recently and found it boring as well.) Fallout New Vegas is sweet, not quite as good as the first two but still rather fun, and maybe the best RPG in a sense to ever come out for a console (not my favorite RPG game that is out for a console... Two different things. I mean KOTOR II is better game to me but not as good of an RPG. To me the best RPGS would be like Arcanum, Fallout 2, even if I found one of those kind of games boring. ) But it seems that the Fallout games did have one really bad game that came out only for consoles that i never bothered playing. Never played Tactics.
Quest for Glory games were awesome puzzle solving RPGs, that even though they had the same practice an individual skill until you get better at it like the Elderscroll games which I find to get very repetitive, I still enjoyed them a lot. For people who didn't play PC games in the early 90s think of an action rpg combined with a Monkey Island/sam and max style game.
But come to think of it most of my favorite western RPGs probably were not part of a series or a sequel hasn't come out yet. Can't even think of a great JRPG Series, most of them even the ones I like have some very bad games in their series.