Final Fantasy Tactics can be played on the Playstation 2. If you wish to play games of similiar design, try games by Nippon Ichi such as Disgaea or La Pucelle: Tactics. If you don't want to use a grid you can also try Phantom Brave or Makai Kingdom.

Also, Front Mission 4 and I believe the prior Front Mission games also have the same gameplay style. All Nippon Ichi games are for PS2, as is Front Mission 4. Not sure what systems all the prior Front Missions are for, I've not played them.