Change date (not sure)
Change the date on your ps2 configuration to 25th december to unlock
apu's xmas car !!! also works on 1st january for krusty!! and halloween.
To get smithers w/Burnse's car
Hold L1+ R1 Press Triangle Twice + Square Twice To Get Smithers Driving
Burnse's Car (You Have To Be On Options)
Unlock all leveles
Press up,up,down,up,up,up,down,down,up,down
Access Nuclear Bus
Go to options menu, hold L1+R1 and press triangle, triangle, square, x
