Resident Evil: I've always enjoyed their characters, story, and general gameplay, but I've never been very good at them. I finished the first one (on the PSOne, not REmake), RE2 as Leon (never the second scenarios though), and RE4 on the 'Cube, but that's basically it.
Virtua Fighter: Supposedly there's some depth to this game, but I never got into it enough to be any good at it. I like instant gratification; Tekken and Street Fighter love me and I love them.
Gran Turismo: Great game, incredible graphics and gameplay, but I've never been able to wrap my head around the "simulator" feel to the driving. I prefer my pedal to the medal action like that found in games like Ridge Racer and Burnout.