I used v 1.2 codes for Giga Bowser
http://arcentral.net/ssbm/ssbmV12/v12vschar.html
And I haven't tried the Debug Mode yet. Which code should I use:
http://arcentral.net/ssbm/ssbmV12/v12debug.html
For the Debug Menu? Well I never played with the regular Giga Bowser without the menu. Get the regular Debug Menu Code and then use that, that way, you can use other extra characters too! You can use 7 super secret characters. Here is what I have to say...
Sandbag: The game will freeze if you use any move so basicly, you can only slide and jump.
Giga Bowser: He's really big and has every move Bowser has.
Popo (solo): There is no nana with Popo, this might be easier or difficult for you.
Female Wire Frame: The Female Wire Frame has no B moves so you can only use the C stick, a buttons, and Z and the Control stick of course. She has Zelda's attacks.
Male Wire Frame: Again, he has no B and you can use any of the buttons and sticks described in the female wire frame. He uses Captain Falcon's moves.
Crazy Hand: Has really cool moves but are hard to control, see the Debug Menu FAQ on a famous FAQ site for the list of moves.
Master Hand: Has really cool moves but are hard to control, see the Debug Menu FAQ on a famous FAQ site for the list of moves.
I think the code you use might not work so well. Most codes tend to freeze. But if you use the Debug Menu, you will not have to see the results screen. Just keep the time mode and time at zero. The game will now be endless! But you can still press the reset combination on your controller while in pause. It never froze my game but it might happen. It's important that you don't have your real GC memory card with your data on it because this code can wipe out your entire memory card. So only use the Action Replay card, don't use one of your own. If you want to know more on the Debug Menu, go to a Debug Menu FAQ that is on many sites. You should find it easily. It most likely has the code incase you had trouble finding it or it wasn't working. So I'm saying, I'd rather use the Debug Menu code (Master Control Debug Menu) on ARC.