I bought Darkensang for $5 during the D2D anniversay sale. Man, I have so many games from that I have yet to download. I keep on forgetting about them.
In a way I wish I had paid more for Drakensang. It would give me more incentive to dig deeper into that game.
I would recomend this one, I play um all (and I do mean all) and its pretty good, bit easy but still fun, keeps that "i need to do this" feeling going, not so open ended that you easily lose sight of the main goal (oblivion, marrowind, I'm looking at you).
Witcher- good game with one major flaw, one of the hardest battles is at start of game, many people never get past it (damn hell hound!). Easily one of the best of the last 5 years IMHO.
Gothics- all good, 3 is pretty amazing looking.
Two Worlds- Oblivion with worse graphics and harder game play and some UGLY bugs. If you liked Oblivion its not to far a stretch from that. Oblivion is better game, but Two Worlds isnt to bad.
Vampire the Masquerade: Bloodlines- also a title that doesnt get enough love as its pretty great game.. when patched! but alot do not classify this as a RPG.
if i had to pick just two i would say WITCHER and Darkensang