When you have a file on your Nintendo DS system. You take the battery out and then put it back in and it should be just like when you first bought it. But if you want to delete a game file on a game you have to ask a separate question that is not what i am answering.
"L+R +x+y+a+start=delete save game!!" (First answer by Shadowpie)
That didn't work for me - however:
I confirmed creating a new game over an existing save, but immediatly after that (before creating/saving a character or anything) I hit the "back" button, the result:
The old game was deleted and the game slot was now displayed as unused/free :)
Press A B Y X L R at the same time it will say do you want to delete the game say yes and it will be deleting the save file it will say delting the saved file do not turn off the power then it will say the game has been deleted then it shows the door and you ring it and go to the kennel to pick a pup. Or, on the home screen on nintendogs, press save it says do you want to save the game say yes it will say saving do not turn off the power turn off the power because on my pok'emon mystery dungeon explores of the sky it was saving i turned it off and i had to start a new game but i was deleting the game so it may work.
if you mean how to delete games saves, you can only do it from the game itself, its in the options most of the times, and if you mean the 3DS hardware you can format you 3DS system memory from the system settings
On the main menu go to options in the bottom right corner and select erase data.
From the game's main menu, go to "Options." From there, select "Erase Data," and say yes when it asks you if you want to delete your saved data.
Go to the license you want to delete, and you'll see a "Settings" option. Go there, and select "Delete License" to delete your save file.
You go to the file you want to delete and then you press delete
At the title screen, press A, B, X, and Y at the same time. Say yes when it asks you if you want to delete your save file.
1.Have a saved file of Super Mario Galaxy 2.Get a one star rank on every 150cc mirror cup.
you go to your file then you go to the top right then you pres it then you will see 3 things on the top it is what your good and not good at the middle is to change your Mii and the last thing is to delete your file.
Here is a cheat just for you... If you have a super Mario galaxy file, you automatically unlock Rosalina for play in Mario kart!
No, you have to have a Super Mario Galaxy save file.
you can't
First of it's not "Rozolina" it's "Rosalina". Sorry I just had to correct that. Anyway to unlock Rosalina in Mario Kart Wii, you have to :Get a "One Star" rank or better in the Wii Cup Series.Alternately, have a saved game file from Super Mario Galaxy and win a few grand pix races.Hope this helped :)
Get a "One Star" rank or better in all Mirror Mode Wii-Cups. Or if you have a saved game file from Super Mario Galaxy, you should win 50 Grand Prix races.
Rainbow Road includes some Mario Galaxy aspects, such as star bits. Also if you have a save file on your Wii with Super Mario Galaxy and Mario Kart Wii you can get a character.
The easiest way to get Rosalina in Mario Kart Wii is to buy Super Mario Galaxy and make a save file in the game. The next time you play Mario Kart Wii, you should have unlocked Rosalina.
You need to play a few levels on Mario Kart.
If you mean saved games you can delete them from the WolfQuest 2 folder. The location of this folder depends on what operating system you use.Where to find your saved games:Windows: [Your Username]/My Documents/WolfQuest 2Macintosh: [Your Username]/WolfQuest 2