So I got a PS2... Please recommend me some games!

[Farsala]

Most obvious answers have been said already so I will add:

Dynasty Warriors 3-5
Romance of the Three Kingdoms 7-11
Dynasty Tactics 1-2
Samurai Warriors 1-2
Onimusha
GTA 3, VC, SA
Bully
Odin Sphere
Twisted Metal Black
Monster Rancher 4