All cameo FMV sequences :
Select Features at the Main menu then select Create-a-Car and enter Seymore Cameos as a case sensitive code to unlock all cameo FMV sequences.

Dale Earnhardt:
To unlock Dale Earnhardt win the Daytona 500 with Kevin Harvick (29 car). A Thunder Plate will appear with Dale Earnhardt on it once you have won or alternately play three Lighting challenges.

All-Star race:
To unlock the All-Star race reach level 16 in your EA Bio.

Bud Shootout:
To unlock the Bud Shootout reach level 18 in your EA Bio.

Night tracks:
At Season mode go to Custom Schedule and you will be able to unlock night races for the day tracks.