If every game was released at once in their current form? I'm thinking BioShock. It's already considered one of the best games ever made due to its artistic merit and acclaimed gameplay; and it's a current gen game, so it wouldn't be looked down upon for inferior technology or whatever.
Don't get me wrong, though: even in this scenario, I think older games that went for stylized visuals over pure technological prowess would receive plenty of acclaim. Chrono Trigger, Yoshi's Island and Okami would receive plenty of love in that situation; but many games considered "groundbreaking" back in the day, like the original Resident Evil and Donkey Kong Country, would fly under the radar.
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CRAZY DAVE (PLANTS VS. ZOMBIES)
Character Battle IX champion. Also, XxmonsterxX is a boss.