What a great non-word.
Anyway, what is "essential" is completely subjective as shown by the varying responses in this thread. For instance:
..as for Devil May Cry. I got DMC3 Special Edition for FREE, and I still felt ripped off. It was just fighting over and over, and I got bored after 30 minutes. Why is this series so loved? Did I miss something?
I loved DMC3, but it isn't for everyone. It's a fighting game so what did you expect from it? It's like buying a basketball game and saying it's just basketball over and over. DMC3 is revered because it's unforgivingly difficult, but not in an unfair way. The controls are precise and there is a good deal of strategy in the game design. DMC3 and Ninja Gaiden are probably the best games of this genre of this console generation.
A game I think that's boring is Dynasty Warriors, but it has its own fans, enough to warrant the five plus games in the series.
I agree with Chacrana, SOTC is the only game on your list I kept. I like GTA, but the Xbox versions are better due to both load time and custom soundtracks (and arguably graphics) although the PS2 versions have better controls.
Other games I liked enough to keep were Yakuza, Space Channel 5, Guitar Hero, Tekken 5, Tekken Tag Tournament, Street Fighter Anniversary Collection, Final Fantasy X, X-2 (I don't care what anyone says, it was a fun game), and XII, Resident Evil 4, Silent Hill 2 and 3, Valkyrie Profile 2, Shinobi (a very underrated game, thoroughly awesome), Ever Blue 2, Macross, Metal Gear Solid anything, Devil May cry series (at $30 for the boxset it was hard to pass up), Front Mission 4, Suikoden 3, 5 and Tactics, Katamari anything, lots of games.