Marvel vs. Capcom 2: New Age Of Heroes Cheats (Dreamcast)

Go in to training mode, choose your players etc.
  when the training starts leave your dreamcast on while you sleep or something.. then
when you wake up 5000+ points will appear!

To easily gain points to buy characters/clothes/levels, you need 2 controllers connected
first, then, go into arcade mode and immediatly press start on the second controller, now
kill the second controller over and over and over, about 10 times, then finish Arcade mode
as you normally would, when you finish it, instead of winning 2,000-3,500 points as
normal, you will gain in excess of 6,000!

All you do is highlight a character and press Y or A at the selection screen.

Use the following to switch between characters in the middle of the game. For example, if
you choose Cable, Ken, then Ryu, but later in the second stage you want Ken to appear
first, hold L for the second character and R for the third character at the versus
screen.