Downgrade PS3 v4.11 to 3.55

Hi
I just bought new slim 320GB PS3 with MOVE bundle offer.It is CECH2501B.
I upgraded to v4.11 accidentally. I didnt know the previous version.Now what i want to do is to play pirated games DVDs and download games from internet and dont want to buy ONLY Original PS3 games.
Please help me what i can to do for this purpose.Thanks

Attached Images

ps3bundle.jpg (169.8 KB)