I would like to catch an Arceus, but I don't know how to use the cheat to obtain an Azure Flute without an Action Replay, which is too risky. How can I catch the Original One without the high risk of my DSI crashing?
The Azure Flute was never distributed. The only ways to obtain an Arceus in a gen IV game were through the following events:
Through a movie giveaway from 17th February 2010 to 28th May 2010.
2009 (America & Japan)
At Toys 'R' Us from 7th November 2009 to 15th November 2009.
And in Japan from 5th November 2009 to 16th November 2009 through a movie giveaway.
Otherwise, you could also obtain it in Gen V games, Black/White through the Pokemon Global Link following a vote from all people across the world. It was available in Japan from 5th November 2010 to 31st January 2011 and 1st February 2012 to 1st May 2012 for USA, Europe and other countries, that's when I got my Arceus.
You can get more details here.