To get all the tracks and movies, type in 'opensesame' with out the speech marks or spaces at the secrets interface (go to the menu under options and select secrets) and select OK. Do the same for the increased speed and accelaration and speed, but put in 'evopower' but again without any special characters. Now you'll go REALLY fast, and on Rezzo (Italy) you'll go so fast down the first straight you'll scrape the tarmac :-)! But that might hurt your car !-|.
Enter the following at the 'codes' section.
Greater Acceleration: EVOPOWER
Comedy Commentary: HELIUMAID
NO Chassis: THATSSTUPID
Flying Carsa In Replays: FLOATYLIGHT
Overhead Camera: DOWNBELOW
Reversed Camera: ONTHECEILING
Underwater Graphics: WIBBLYWOBBLY
Psychadelic Graphics: IMGOINGCRAZY
For super speed, without using cheat evopower,
simply press the X button with a lot of power,