like Pokemon soulsilver and heartgold, you press down on the control pad, the select button and then b button.
you can't i tried trust me. if you did delete your saved file and you had a Pokemon in the walker it will be there until the battery dies get a new one.
You have to go to the title screen (it has HO-OH for HeartGold, LUGIA for SoulSilver) and press Up, Select, and the B button at the same time. Then a message will pop up asking if you want to delete your game.
by relessing it
You press 'Up' on the control pad , press 'select',and then press 'B' at the same time on the title screen to delete your save file.
You can delete it by clicking it and pressing delete duhhh -miraih snipes
To delete the file: Select+Up+B at the menu screen. Start a new file: Just press "New Game"
Go to the Pokemon center and in the PC select a Pokemon and click release
you cant delete your Pokemon from your party directly but you can deposit them into the PC at the Pokemon center or you can release them if you wish to get rid of them the option is in your PC i do believe.
Click new game at the menu
The only way to delete moves is through the Move Deleter, which should be in Blackthorn City.
Hold B, Select, and either Left or Right.