generally speaking i have found that if you hit the start button and it clicks its bad battery and if like ludador said it hums its starter when it does nothing its a solenoid issue.

 

I agree with HIMSA169. That smoking issue is not good. I'll bet the starter is toast. I read up on my manual when I replaced the flywheel on mine to check the starter clutch. That if it hangs it will tear up the starter. Not sure what that is like but a starter/alternator repair shop might be able to test your starter. Otherwise if you go to a dealer shop they will want to start ordering new parts. Good luck.

 

Bad grounds and bad + connections are probably the cause of the smoking. I would go through and clean ALL the conections with a wire brush.

Ryan