It depends on which system you are playing on. i have mine for the psp and i recommend Burnout Legends.
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Burnout 2 in my own opinion is better to play when you feel like actual, normal racing. If you feel like having an aggressive race with a bit more to it, though, then try burnout 3. i.e. play burnout 2 if you like classic racing, otherwise burnout 3.
Burnout paradise is a game focused more on free roam than anything else. Blur is more focused on the races. I personally think the multiplayer on blur is better than on burnout paradise, because you can level up and get new things, but burnout paradise has good multiplayer too.
split/second is more focused on single races. burnout paradise is focused on free roam challenges and just generally driving around and messing about. You decide.
wolfteam is better
lucario is better