There’s literally hundreds of great PS2 games you could play, but I’m going to recommend stuff I played last year

Onimusha: Warlords (You can tell the first game was built on the template of the first Resident Evil and it’s fun to spot the similarities despite the shift in genre. I also got a kick out of playing a PS2 game with pre-rendered backgrounds. Warning: it’s a melee combat game with fixed camera angles and tank controls.)

Onimusha 2: Samurai’s Destiny (Still uses the first game’s formula. The first game was pretty short and confined to a single castle, the sequel is a more sprawling adventure)

Onimusha 3: Demon Siege (The series moves to full 3D and slightly towards character action, also Jean Reno is in it)

Onimusha: Dawn of Dreams (A soft reboot for the series which brings a shift in tone and art style as well as gameplay, playing like an action RPG)

You should also take the opportunity to play the rare survival horror game holy trinity as a middle finger to the ridiculous prices these games go for on the second hand market

Haunting Ground (Easily the easiest game of the three to recommend. One of the prettiest games on the PS2 and the gameplay is nice and polished. Has one of the greatest dog companions in gaming)

Kuon (From Software’s PS2 horror game set in the Heian period. You can definitely see they weren’t working with a AAA budget- there’s no facial animation during cutscenes, for example, but the various spells you can use make for interesting survival horror combat system and the atmosphere and story are great)

Rule of Rose (A unique female-focused video game narrative dealing with topics you don’t usually see, like bullying. Genuinely emotionally affecting story, atmosphere and soundtrack. Sadly, the gameplay is not that great but hey, there’s a dog companion in this game too)