Bard's Tale - Funny as hell, especially if you have played some of the PS2's action RPG library already. The witty humor and ability to cast creatures to fight with you save this one from being a copycat to games like Baldur Gate or Champions of Narrath.

Blood Will Tell - Awesome game that has you fighting demons to regain body parts (in the beginning of the game you can only see in black and white until you defeat the first demon and regain your eyes.) The story is above average for a hack n' slash game, and there are plently of weapons to collect (including an upgradable cannon implanted in your knee and machine gun in your arm).

The Punisher - In my top 10 PS2 games. This game is just plain great. Contains one of the greatest scenes in a video game when you pop out of a coffin at a funeral parlor and just start unloading lead into anything that moves. It also contains some great death animations like throwing a guy head first into a bear trap or holding a thug against the rhino cage to watch him get impaled.

I'll add some more when I get home from work as I can't access my entire collection list.