Tokyo Xtreme racer is a favorite of my brothers for driving action...pick it up cheap.
Of course, if you truely want the driving experience, definetely-with the highest of recommendation-go get Gran Turismo 3. Gran Turismo 4 is right around the corner, with internet play OMG!
As far as RPG's go, can't go wrong with Final Fantasy X, or XenoSaga if you want something a little linear and mostly set in outer space ( it's good, but falls short of the mark set by FFX )
SSX Tricky is a great Arcade type game, easy to figure out, a little tricky to get used to initially, but you'll be hanging huge air once you get used to the controls. Again, SSX Tricky 2 is right around the corner...w00t! Pick this one up for $20 or less.
Metal Gear Solid 2: Sons of Liberty has an excellent story line..the ending was nothing that I expected! Gameplay=awesome. Nothing like sedating your enemy and dragging them around and putting them into compromising positions, or throwing them overboard
Of course, you have your Crash Bandicoot games...blah blah blah.
Rachet and Clank is a good adventure game, and so is Jak and Daxter.
Beyond that, I haven't been really following the PS2 console games as closely lately ( I just got BF1942, which I'm off to play! C'mere B-17 bomber!

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