In the options menu highlight the "time limit" option. Hold A and left until it reads 00. Now the timer will be blank and the fights will only end when a fighter is knocked out.This cheat works in any mode.
Complete the 1 player game mode under the hard difficulty level setting without using a continue. The ending will have an additional sequence showing all of the fighters.
At the continue screen enter the following code....
Hold Start and press A + B + C
Doing this will give you one more continue
Note: This can be done up to nine times in one continue.
Usually in the player vs. CPU mode, the CPU will randomly select a character for you to fight against. However, whilst highlighting the 1P VS COM, hold the C button on pad 2. With C held down on pad 2, press start on pad 1. You'll now go into the character select screen, and you can choose who you want to fight by using pad 2 to move through the fighters.