i rotate my tires every 5000 miles and get it aligned once a year just to be sure its ok.. i rotate by taking the rear and crossing them to the front and bring the front tires straight back.
i just put a new battery in my 1999 and everything worked fine , even after being disconnected for about 20 min. i was also worried about my radio but was told this year rx300 does not code radio. just had to reset clock and radio stations.
try cleaning your throttle body using a good fuel injection cleaner. i also agree with the others about using good fuel cleaner in you gas. good luck from the bug man