Tales of Symphonia is the best in the tales series.
Graphics: Tales of Symphonia's graphics are good. They'd still be considered fairly well done to this day. The anime, though, is just amazing. The cutscenes give off a kind of old feel. And the character designs are done by the incredible Kosuke Fujishima who never fails.
Battle system: The battle system for this game is quite good. It's easy to understand, but it's not boring. You can choose from 9 characters (8 at a time) to play as, and 3 others to fight alongside you. You can use items, change techs, create combos, equip, and use unison attacks which allow attacks one after another. Movement in battle is linear, but doesn't take away much.
Gameplay: You can choose who to walk as, and go from city to city, and dungeon to dungeon. All cities are distinct. The dungeons may pose quite a challenge on the first playthrough, forcing your brain to work.
Story: The story of Tales of Symphonia is an excellent story filled with emotion. The plot has a number of twists that will keep you interested with the sometimes long dialogue. There is excellent replay value as you can see different people's pasts based on how you choose to go through the game.
Characters: What makes Tales of Symphonia just so good is it's characters. It's characters who are unique, vibrant, and just plain realistic. They keep the dialogue interesting and stops the game from just dragging.
Tales of Symphonia is the perfect role playing game that will forever remain a favourite to many.