Definitely get DMC 1 and 3 and all the Jak/Sly/Ratchet games (well, maybe not deadlocked)
Which Grandia is it?
2 is a pretty good RPG although it's like the easiest one ever and the PS2 version has a few porting issues I hear, 3 is often criticized for bad writing (as in characters disappear and are never heard from again), and XTREEEEEEEEEMMMMMMEEEEEEEEEEEEE is a dungeon crawler (though I haven't played the latter two yet and played the former on the DC).
also which .hack is it?
not that it really matters since I wouldn't really recommend it since both series are basically one game split over multiple installments by repeating the same filler quests and such (like winning the arena) over and over in each installments, and there's a lot of multimedia spinoffs. The GU trilogy is much better than the original IMOQ series though.
edit: whoops you already made your purchase
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The only certain death in the universe is Mother Hitton's Littul Kittons.
Not changing this line until I beat Seven Heroes (2/24/07)