I would say Heavy Rain or Mirror's Edge ... if you are looking for more action play Mirror's Edge first, and if you don't want much gameplay or player commitment then do Heavy Rain first.
Everything else on there is either bad or average. Maybe play Duke Nukem Forever after the other two. It is not nearly as bad as people make it out to be, and, in some ways, it is better than most modern shooters because it does away with annoying things that have become staples of the genre while including features that other shooters neglect (no aiming down gun sights, mini games that break up the gameplay and add variety, lots of humor which is hit or miss but mostly passable, a story that does not revolve around shooting russians or terrorists, wacky weapons and powerups)
I would say $300 sounds about right for all of those, but I don't think you got much of a deal on these. I would go as far as to say that you got ripped off if the majority of those games are not in flawless/new condition with original cover art/manual/case.